Speaker 1: Get in touch with technology with tech Stuff from how
Speaker 1: stuff works dot com. Hey there, and welcome to tech Stuff.
Speaker 1: I'm your host, Jonathan Strickland, senior writer for how stuff
Speaker 1: Works dot com, and today I thought it might be interesting.
Speaker 1: So perhaps I'm mistaken to talk about data storage, specifically
Speaker 1: magnetic storage. So there are a lot of different ways
Speaker 1: to store data, you know, like there's always writing it down,
Speaker 1: that's the type of data storage all the way up
Speaker 1: to like holographic memory storage. And magnetic storage has played
Speaker 1: a really important role in the history of technology in
Speaker 1: general and computers in particular. So I want to focus
Speaker 1: on how magnetic storage works. Who came up with that
Speaker 1: idea and even dive into the science of magnets. Yes,
Speaker 1: insane clown posse, I'm looking at you. We're gonna discover
Speaker 1: how magnets work. So if you've been wondering since that
Speaker 1: video I got, I got your hook up. So first,
Speaker 1: let's talk about why magnetic storage was a necessity in
Speaker 1: the first place. So how do you preserve information so
Speaker 1: that you can access it again later? Because in the
Speaker 1: old days, and I'm talking like tens of thousands of
Speaker 1: years ago, verbal communication was where it was at you
Speaker 1: stored all that information up in your head. Someone would
Speaker 1: tell you something important and you had to remember it.
Speaker 1: Perhaps they would tell you within the context of a story.
Speaker 1: And then eventually, if you were trying to preserve information,
Speaker 1: you would tell that same information to someone else and
Speaker 1: pass it along. This way, this is essentially folklore. That's
Speaker 1: how knowledge was maintained for centuries. And then way back
Speaker 1: in the day, someone said, hey, what if we made
Speaker 1: up some symbols to represent these sounds we're making to
Speaker 1: communicate with each other, and then we put those symbols
Speaker 1: into some sort of fixed format, like in a clay tablet,
Speaker 1: And that way we can preserve the information a lot longer.
Speaker 1: And if Bob, who's really good at making fires, can
Speaker 1: explain how to make fires, and we we put it
Speaker 1: down in this format, we'll be able to make fires
Speaker 1: even if Bob does something stupid like walks off the
Speaker 1: edge of a cliff or something. And writing was born.
Speaker 1: It probably went a little differently from the way I
Speaker 1: explained it, but I think I got the gist of it.
Speaker 1: Not everyone, however, was a fan of this development. Believe
Speaker 1: it or not. There were people who were against the
Speaker 1: whole idea of writing stuff down. Socrates was actually a
Speaker 1: critic of writing stuff down, or at least that's what
Speaker 1: we hear, because Socrates didn't write anything down, his students did. Uh.
Speaker 1: He said that the written word is fixed, and therefore
Speaker 1: it can't defend itself or any arguments it makes, so
Speaker 1: it's inherently flawed. If someone writes down an argument and
Speaker 1: your access to the argument is in that written format,
Speaker 1: and you have questions or you have attacks on that argument,
Speaker 1: it can't defend itself. The person who wrote it could
Speaker 1: if they were there, but if they're not there, then
Speaker 1: the argument has to stand on its own, and therefore
Speaker 1: it has to be less effective. Let's say that an
Speaker 1: actual human being. He also said that if you write
Speaker 1: stuff down, you don't have to remember it yourself, and
Speaker 1: that makes you less intelligent, because if you're not actually
Speaker 1: committing something to memory, you're getting super dumb. Uh. This
Speaker 1: might sound a lot like some of the arguments people
Speaker 1: have made about Google and the Internet, and it's absolutely correct.
Speaker 1: Every single time we have created a new way to
Speaker 1: permanently store data in some form or another, people have
Speaker 1: brought up this idea that it's making us more dumb,
Speaker 1: Like they might say, hey, Back in the day, you'd
Speaker 1: have to remember all your phone numbers, like all the
Speaker 1: numbers of the friends and family that you would be
Speaker 1: calling a regular basis. But now it's all on your phone,
Speaker 1: so you don't remember it. You may not be able
Speaker 1: to rattle off more than two or three phone numbers
Speaker 1: today because of that, therefore you are more dumb. I
Speaker 1: don't subscribe to that particular argument. I think having the
Speaker 1: accessibility of information outweighs the fact that we are no
Speaker 1: longer able to remember it necessarily. Uh. The point I
Speaker 1: would make is that comprehension is always more important than
Speaker 1: being able to recall something. You might be able to
Speaker 1: recall some information, but if you don't truly comprehend it,
Speaker 1: it's no It's of no use to you. So I
Speaker 1: don't think it's necessarily a measure of intelligence. It's certainly,
Speaker 1: perhaps more of a statement about our memories than anything else.
Speaker 1: But I'm getting off on a tangent here. So I
Speaker 1: think the developments we've had have been phenomenal. We wouldn't
Speaker 1: be where we are today if we were still depending
Speaker 1: upon just telling each other the important stuff and hoping
Speaker 1: that they would be able to then tell other people
Speaker 1: the important stuff we just told them and in way
Speaker 1: that was accurate and effective. We clearly wouldn't be where
Speaker 1: we are today if we still depended upon that. And
Speaker 1: I don't have to travel all the way across the
Speaker 1: world to find a specific guru to learn how to
Speaker 1: perform a particular skill. I can just go onto YouTube
Speaker 1: and watch like thirty or forty videos until I find
Speaker 1: one that actually makes sense. So that's progress. Take that, Socrates. Now,
Speaker 1: throughout history, we saw many advances in the way we
Speaker 1: store information, and as we developed more advanced technology, it
Speaker 1: became clear that a compatible method of storing data would
Speaker 1: be really handy. So imagine what computers would be if
Speaker 1: they could not save information, they'd be practically useless. You
Speaker 1: need to have a way of storing data somehow, whether
Speaker 1: it's in magnetic storage, optical, solid state punch cards, whatever.
Speaker 1: You need something that can record the information otherwise it's
Speaker 1: only good for a moment. And a lot of folks
Speaker 1: worked on this problem, and as is the case with
Speaker 1: many technological developments, some of that work had nothing to
Speaker 1: do with computers, but more with researching fundamental scientific questions
Speaker 1: and finding answers to questions lead other people being able
Speaker 1: to use that information in practical ways that we didn't anticipate.
Speaker 1: And this is kind of another soapbox I like to
Speaker 1: get up on, uh to argue for the importance of
Speaker 1: exploratory science. Applied science is really interesting. Applied sciences when
Speaker 1: you're trying to find a particular solution that will work
Speaker 1: for some sort of problem. Right your you might be
Speaker 1: researching whether or not a specific material would be great
Speaker 1: to use for a particular purpose, like bulletproof material something
Speaker 1: like that. But exploratory science, when you're not necessarily looking
Speaker 1: for applications, is also important because we expand our knowledge
Speaker 1: about how the universe works, and it can open up
Speaker 1: opportunities to leverage that knowledge in ways we could not
Speaker 1: have anticipated when we first started looking into the issue
Speaker 1: in the first place. It's in and stuff, So I
Speaker 1: argue that exploratory science needs to continue to be supported.
Speaker 1: Let's uh now acknowledge all this, take a deep breath,
Speaker 1: and get ready to jump into the strange world of magnetism. So, first, magnetism,
Speaker 1: or more specifically, electro magnetism, is one of four fundamental
Speaker 1: forces that govern the atomic behavior in our universe. So
Speaker 1: the other three if you're keeping track, are the strong
Speaker 1: nuclear force, the weak nuclear force, and gravity, And if
Speaker 1: you want to rank those from the weakest to the strongest,
Speaker 1: you'd start with gravity. Gravity is negligible at the atomic scale.
Speaker 1: It's there, but it's so faint as to be almost absent.
Speaker 1: And this is largely because gravity is dependent upon mass,
Speaker 1: So at the atomic scale, mass masses are so small
Speaker 1: there's barely any gravitational attraction between particles. But gravity is
Speaker 1: kind of nifty because while it's weak, it is there.
Speaker 1: And in fact, there's a gravitational pull on every bit
Speaker 1: of matter from every other bit of matter in our universe.
Speaker 1: So you, that is you listening to me right now,
Speaker 1: you are are exerting a gravitational pull on the Sun,
Speaker 1: and on Alpha Centauri, and on the Andromeda galaxy. You
Speaker 1: are exerting a gravitational pull on everything else that is
Speaker 1: matter in our universe. It's just that that gravitational pull
Speaker 1: is so weak as to be practically nothing, but it
Speaker 1: is there. So since gravity is something we ourselves can
Speaker 1: and do experience in our daily lives, we categorize it
Speaker 1: as one of the familiar forces. Now, next in the
Speaker 1: rank from weakest to strongest, is the weak force. Now
Speaker 1: that's responsible for nuclear beta decay and some other decay processes.
Speaker 1: And this one's pretty difficult to explain. And since I'm
Speaker 1: are you going to have to explain magnetism, I'm gonna
Speaker 1: call for a pass on this one. Let's mulligan it.
Speaker 1: But this is a force that we do not experience
Speaker 1: firsthand in our daily lives, So this one actually falls
Speaker 1: into the category of unfamiliar forces. Now next in strength,
Speaker 1: so second strongest if you prefer, is the electromagnetic force,
Speaker 1: the one will be focusing on today. Now, this is
Speaker 1: a force that exists between all particles that have an
Speaker 1: electric charge. So electrons, for example, will bind to a
Speaker 1: nucleus because electrons have a negative charge, and a nucleus,
Speaker 1: which only contains positively charged protons and neutral neutrons, is
Speaker 1: net positive. And you know that opposites attract, so we
Speaker 1: have the negative electrons attracted to the positive nucleus. We
Speaker 1: can and do experience electromagnetic forces on a daily basis,
Speaker 1: so this one is one of the familiar forces. And
Speaker 1: then we have the strongest of them all, all the
Speaker 1: strong nuclear force. This is the force that holds a
Speaker 1: nucleus together it's a dominant force in various chemical reactions,
Speaker 1: and it has to be strong because it's doing something
Speaker 1: that's really difficult to do. It's holding together similarly charged particles. Remember,
Speaker 1: a nucleus is a bunch of protons and neutrons. The
Speaker 1: protons all have a positive charge. They don't want to
Speaker 1: be and when I say want, I don't actually mean
Speaker 1: they have motivations, but they don't want to be next
Speaker 1: to each other. Those parts, those similar charges are repelling
Speaker 1: one another. So the strong nuclear force has to be
Speaker 1: stronger than the electromagnetic force in order to hold protons
Speaker 1: together in a nucleus with a bunch of neutral charge particles. Ah,
Speaker 1: it does have a very short range, however, so while
Speaker 1: it's stronger than the electromagnetic force, it does, the range
Speaker 1: does not reach very far outside of a nucleus, so
Speaker 1: we do directly observe it in our daily lives, and
Speaker 1: therefore it is an unfamiliar force. So gravity and electro
Speaker 1: magnetism are familiar forces. The strong and weak nuclear forces
Speaker 1: are unfamiliar forces. Uh So what makes electro magnetism tick
Speaker 1: and how did we even figure out how to make
Speaker 1: good use of it? Well, let's start by imagining a
Speaker 1: bar magnet. A lot of this is going to go
Speaker 1: back to stuff that you probably learned in elementary school,
Speaker 1: middle school, high school, those physics courses, that kind of stuff,
Speaker 1: basic science. So you've got your bar magnet. Uh, let's
Speaker 1: just say it's a rectang. It's rectangular in shape. So
Speaker 1: you know you've you've got uh, your north pole and
Speaker 1: your south pole on the magnet. Um this these represent
Speaker 1: the various charges, magnetic charges of the magnet, opposites tracked.
Speaker 1: So if we were to bring this bar magnet close
Speaker 1: to another bar magnet, the north end of our bar
Speaker 1: magnet would start to exert a poll on the south
Speaker 1: end of the other bar magnet. Or if we were
Speaker 1: to try and bring the north pole of our magnet
Speaker 1: close to the north pole of the second magnet, it
Speaker 1: would push against each other, just like I was mentioning
Speaker 1: a second ago. Now, magnets produce a field around them
Speaker 1: that we can represent as lines of force, and those
Speaker 1: lines exit from the north pole, loop around the magnet
Speaker 1: and enter the south pole. A permanent magnet is always
Speaker 1: producing the sort of magnetic field. It's it's consistent, it
Speaker 1: doesn't waiver. Um. You may hear about things like electromagnetism.
Speaker 1: I'll talk a little bit more about in a in
Speaker 1: a bit, where you have to move a coil through
Speaker 1: a varying magnetic field, will a permanent magnet creates a
Speaker 1: consistent magnetic field unless you start doing things like moving
Speaker 1: it around, in which case you're really just moving where
Speaker 1: the magnetic field is. You're not actually fluctuating the field itself. Now,
Speaker 1: inside a magnet a permanent magnet are microscopic regions called
Speaker 1: magnetic domains, and each of these domains is essentially a
Speaker 1: tiny magnet with its own north and south pole. Only
Speaker 1: by aligning the poles of all of these uh magnetic
Speaker 1: domains in a similar direction, like north south, will you
Speaker 1: get a permanent magnet. So if you could just zoom
Speaker 1: in on a permanent magnet, you would see all these
Speaker 1: tiny regions that are essentially magnets that are all aligned
Speaker 1: the same way north south. If you didn't do that,
Speaker 1: if the alignment was mixed up so that you had,
Speaker 1: you know, an equal mixture of north south and south north,
Speaker 1: they would cancel each other out and you wouldn't have
Speaker 1: a magnet. It would just be inert magnetically speaking. So, uh,
Speaker 1: that is something that's interesting because you can actually do
Speaker 1: that to magnets in a couple of different ways. I'll
Speaker 1: talk about that in a second. So all of that
Speaker 1: is changeable. Bomb bom bomb. I wrote that in my notes.
Speaker 1: Actually I had to say it. I could show Dylan,
Speaker 1: but he's working on something else. By the way, when
Speaker 1: all those magnetic domains are aligned north south, what happens
Speaker 1: if you were to cut the magnet in half right
Speaker 1: between the north and south pole. So imagine you've got
Speaker 1: this rectangular bar magnet. You've got you've labeled one in
Speaker 1: the north pole, the other in the south pole. You
Speaker 1: cut the magnet in half horizontally across, well, you would
Speaker 1: end up with two magnets. The middle of that magnet
Speaker 1: would become the south pole for the north end and
Speaker 1: the north pole for the south end. That's because those
Speaker 1: magnetic domains I was talking about, those tiny regions inside
Speaker 1: the magnet themselves itself, those are all aligned north south.
Speaker 1: So if you cut the magnet across, you still have
Speaker 1: those magnetic domains lined up north south, so the overall
Speaker 1: magnetism is preserved. You get two magnets for the price
Speaker 1: of one, but don't cut into magnets magnets, they tend
Speaker 1: to be at least the ones that we typically use
Speaker 1: for things like our fridges and stuff are ceramic magnets,
Speaker 1: and they don't cut so well unless you have like
Speaker 1: a a diamond saw, which some of you probably do.
Speaker 1: And and if you cut magnets normally, then disregard my warning.
Speaker 1: I'm talking about people who don't typically do that sort
Speaker 1: of thing. If you are going to do it, where
Speaker 1: eye protection because that stuff can shatter anyway. Uh, if
Speaker 1: you do that with the magnet. Essentially, each magnet has
Speaker 1: approximately half the magnetic domains of the old magnets, so
Speaker 1: they're not particularly you know, the the individual magnets aren't
Speaker 1: as strong as they were when they were a single magnet.
Speaker 1: Because you're you're magnets, You're overall magnet strength is dependent
Speaker 1: upon the accumulative effect of the magnetic domains within it,
Speaker 1: all right, So each of those magnet domains are tiny magnets.
Speaker 1: There are three ways to get them to line up
Speaker 1: so that the overall material becomes a magnet itself. Like
Speaker 1: how you get them all to line up like north south?
Speaker 1: So way number one is to whack on it with
Speaker 1: something heavy, which isn't a joke. If you hold the
Speaker 1: material in the north south direction and strike it with
Speaker 1: a hammer, you physically realign the magnetic domains and you
Speaker 1: can knock the material into a weak magnet. There's a
Speaker 1: bit more to it than that, but that's the basic idea,
Speaker 1: and that that does mean that you're not going to
Speaker 1: get a very strong magnet as a result, but you
Speaker 1: can physically force those magnetic domains to be in the
Speaker 1: same direction and create a magnet that way. Way number
Speaker 1: two is that you can place the material inside a
Speaker 1: strong magnetic field and make sure the material is in
Speaker 1: the north south alignment and you just leave it there
Speaker 1: and if it's a strong magnetic field, it will start
Speaker 1: to realign the magnetic domains within your target material so
Speaker 1: that they gradually line up with the magnetic fields direction.
Speaker 1: So you just have to have a strong enough one
Speaker 1: to affect the magnetic domains in your target material and
Speaker 1: then eventually you end up with a magnet. So that's
Speaker 1: kind of cool. And way number three is yes, zap
Speaker 1: it with electric current. So one hypothesis is that this
Speaker 1: is how loadstone, which is a naturally magnetic material you
Speaker 1: can find here on Earth, was originally formed the ideas
Speaker 1: that loadstone, which is made up of this stuff called magnetite. Uh,
Speaker 1: some of it was struck by lightning over the the
Speaker 1: the millennia that Earth was forming. So you have magnetite
Speaker 1: on the surface of the planet. Occasionally lightning strikes and
Speaker 1: hits some of this magnetite and then magnetizes it. That
Speaker 1: was That's one hypothesis. But there's another one which suggests
Speaker 1: that magnetite gained its magnetic properties during the time when
Speaker 1: Earth was forming, and it was through more of a
Speaker 1: just a physical uh, the physical process of cooling where
Speaker 1: these magnetic domains aligned in the proper way. Here's the thing,
Speaker 1: we don't really know how it all got started. We
Speaker 1: don't have that information. No one was around back then
Speaker 1: to write it down or put it in magnetic storage.
Speaker 1: So it's still a bit of a mystery. But we
Speaker 1: do know that those are two possible ways that this
Speaker 1: could have come about. And uh, you can also render
Speaker 1: magnets inert by changing the alignment of the magnetic domains
Speaker 1: within it. If you heat a magnet up beyond its
Speaker 1: cury point, which is different for different magnetic materials, it
Speaker 1: loses its magnetism. The heat warps the material and makes
Speaker 1: the magnetic domains fall out of alignment. So what used
Speaker 1: to be magnetic will no longer be. So something that
Speaker 1: would stick to your fridge no problem, will just slide
Speaker 1: off and hit the floor, and everyone will be sad,
Speaker 1: unless you just did it as a scientific experiment, in
Speaker 1: which case you might be happy that you've got the
Speaker 1: result you expected. Now we can experience magnetism because of electrons.
Speaker 1: This time, negatively charged sub atomic particles hold the key
Speaker 1: to whether a material is affected by magnets or isn't.
Speaker 1: You know, might wonder like, why are some things magnetic
Speaker 1: and some things aren't? Why do magnets stick to some
Speaker 1: materials but slide right off of other materials? And ultimately
Speaker 1: the answer falls with electrons. Now, electrons orbit the nucleus
Speaker 1: right in the atoms. You remember your basic description of
Speaker 1: an atom, where you have a nucleus at the center
Speaker 1: and electrons orbiting at different orbital shells around the electrons. Typically,
Speaker 1: electrons will pair up with other electrons. You'll get pairs
Speaker 1: of electrons. They have a state that's called spin, and
Speaker 1: each electron in a pair has the opposite spin of
Speaker 1: its partner. So we can describe spin as up or down.
Speaker 1: For example, if one electron is spinning up, the other
Speaker 1: one by necessity has to be spinning down. You cannot
Speaker 1: get both electrons in a pair to spin in the
Speaker 1: same direction in the same orbital That just that ain't cricket.
Speaker 1: It's part of the quantum mechanical principle we call the
Speaker 1: poly exclusion principle. And until I did a research for
Speaker 1: this show, I could have sworn that referred to the
Speaker 1: practice of non inviting Polly shortier parties. So I guess
Speaker 1: you've learned something new every day. That got a smirk
Speaker 1: from Dylan. It's maybe he'll laugh when he listens to
Speaker 1: it the second time. Uh. Some elements have an unpaired
Speaker 1: electron in an orbital just because that's just how it
Speaker 1: works out. So those unpaired spinning electrons generate a very
Speaker 1: tiny magnetic field, and we call it an orbital magnetic moment,
Speaker 1: which sounds like something you'd expect in a romantic science
Speaker 1: fiction film. Iron, for example, has four unpaired electrons that
Speaker 1: all have the same spin. Those four unpaired electrons have
Speaker 1: an orbital magnetic moment. So magnetic moment has a magnitude
Speaker 1: and the direction, which means it is a vector. The
Speaker 1: bottom line is this vector refers to the strength of
Speaker 1: the magnetic field and the torque it can exert. So
Speaker 1: a permanent magnets magnetic moments are composed of all the
Speaker 1: moments of its atoms. In other words, you've got all
Speaker 1: these atoms that represent an orbital magnetic moment because of
Speaker 1: the spin of the electrons of the unpaired electrons. If
Speaker 1: you've got enough of them and they're aligned the right way,
Speaker 1: that determines the permanent magnets magnetic moments. So iron and
Speaker 1: several other magnetic elements have a crystalline structure, right, so
Speaker 1: think of it like scaffolding. It makes this very ordered
Speaker 1: kind of structure as opposed to something that looks much
Speaker 1: more chaotic. So as iron cools from a molten state,
Speaker 1: atoms line up into this crystalline arrangement, and groups of
Speaker 1: atoms that have a parallel orbital spin will line up
Speaker 1: within the crystal and those form those magnetic domains I
Speaker 1: mentioned earlier. The qualities that make good magnets are also
Speaker 1: the same ones as the qualities that make materials attracted
Speaker 1: to magnets. So a strong magnet will attract iron and
Speaker 1: other elements that have these orbital magnetic moments in alignment. Now,
Speaker 1: not all permanent magnets are equal. The ceramic magnets you
Speaker 1: may have on your fringe door a pretty weak all
Speaker 1: things considered. They're made of a mixture of iron oxide
Speaker 1: and a ceramic composite. These are ferric magnets, that's what
Speaker 1: we call them, ferric for the iron that's in them.
Speaker 1: But on the other end of the scale are neodymium magnets,
Speaker 1: a rare earth element magnet there is much much stronger
Speaker 1: than the ferric magnets we tend to use, and they
Speaker 1: typically contain a mixture of neodymium, iron and boron. They
Speaker 1: could be really strong too, uh, I have played with somewhere.
Speaker 1: If they get into contact with something like a metal table,
Speaker 1: it can be really hard to remove them. We had
Speaker 1: some here at how Stuff Works that were potentially causing injuries. Uh.
Speaker 1: One person slipped one in their pocket and then found
Speaker 1: themselves stuck to a filing cabinet for a little bit. Uh.
Speaker 1: This was way back in the day, but it was
Speaker 1: one of those things where a lot of us didn't
Speaker 1: have a whole lot of experience with it because at
Speaker 1: the time they were fairly uncommon. Today you can order
Speaker 1: neodymium and other rare earth magnets online without much trouble.
Speaker 1: But when I started um, first of all, how stuff
Speaker 1: works was easy because there are only three things, so
Speaker 1: it was easy to explain how stuff works. Once you
Speaker 1: wrote the three articles, you were done. But over time
Speaker 1: more stuff was made and we had more work to do,
Speaker 1: and at that point it was more. It was more
Speaker 1: uh uh, well, it was easier to get ahold of
Speaker 1: neodymium magnets at that point. Now, some materials are called
Speaker 1: temporary or soft magnets, and those will produce a magnetic
Speaker 1: field in the presence of another magnetic field and retain
Speaker 1: some of that magnetism for a while after they leave
Speaker 1: the field itself, so they're very easy to LUNs. So
Speaker 1: imagine that you've got something like a paper clip and
Speaker 1: you put it within the range of a magnetic field
Speaker 1: for a while, and it starts to have its magnetic
Speaker 1: domains aligned according to this magnetic field. You remove it
Speaker 1: and you find you can pick up other paper clips
Speaker 1: with it, but only for a little while, and then
Speaker 1: it stops working. That's that's very typical with soft or
Speaker 1: temporary magnets, they very quickly will change, but then they
Speaker 1: will over time change back to being, let you know,
Speaker 1: not magnetic. But if they're also hard magnetic materials, these
Speaker 1: it's harder to change them, but then they will stay
Speaker 1: changed for longer. So stuff like iron, if you're able
Speaker 1: to really realign those magnetic domains and iron magnet will
Speaker 1: hold that magnetic ability much much longer. And that's how
Speaker 1: you can end up with permanent magnets as opposed to
Speaker 1: some that will just temporarily be magnetic. Um it's kind
Speaker 1: of interesting. Uh. So then you've got electro magnets and
Speaker 1: this will only produce the magnetic field in the presence
Speaker 1: of electricity. And I'm sure everyone listening to this has
Speaker 1: done some variation on the the experiment where you take
Speaker 1: an iron nail and you coil some wire around it,
Speaker 1: usually some insulated copper wire around the nail several times, uh,
Speaker 1: and then you run an electric current through the wire
Speaker 1: and you create an electro magnet. The nail becomes magnetic
Speaker 1: and you can pick up all sorts of stuff with it.
Speaker 1: The strength of the magnetic field is dependent upon the
Speaker 1: number of coils around the nail as well as some
Speaker 1: other factors, but that's the primary one. Uh. And UH,
Speaker 1: you know it's it's a cool, little basic science experiment
Speaker 1: you can run, but it's also the basis of a
Speaker 1: ton of the work done in electrical fields, including general electronics, computers, storage.
Speaker 1: It is an important fundamental piece of technology. UH. And
Speaker 1: the very simple applications of this you can find in
Speaker 1: stuff like electric transformers or electric motors and dynamos. Like transformer,
Speaker 1: you can have two different coils of wire, one that
Speaker 1: is got a lot more coils to it, uh, like
Speaker 1: maybe twice as many as the second one, And when
Speaker 1: you run a current through the the larger number of coils,
Speaker 1: the magnetic field it generates induces electricity to flow through
Speaker 1: the second set of coils, but steps down the voltage
Speaker 1: because you have half as many coils around a core
Speaker 1: as you do with the first one. Uh. That's how
Speaker 1: you can step down or step up voltage. And that's
Speaker 1: why alternating current ends up being much more effective for
Speaker 1: distributing electricity across the distances than direct current, because you
Speaker 1: can't do that with direct current. You need that alternating
Speaker 1: electric current in order to create the magnetic field that
Speaker 1: will induce electricity to flow through a separate set of coils.
Speaker 1: Just like you need a varying magnetic field to induce electricity,
Speaker 1: you need that varying electricity to produce a varying magnetic field.
Speaker 1: It's this interesting relationship, a fundamental relationship in our universe
Speaker 1: between electricity and magnetism. And uh, that's why I was
Speaker 1: saying before. If you have a permanent magnet and you
Speaker 1: just put it next to a coil of wire, it's
Speaker 1: not going to induce electricity to flow apart from when
Speaker 1: you first introduce the magnetic field to the coil, because
Speaker 1: it's not varying. You'd have to spin the the permanent magnet,
Speaker 1: which would uh, you know, effectively, according to the coil's perspective,
Speaker 1: change the alignment of that magnetic field. That would induce
Speaker 1: electricity to flow through the wire. But just having a
Speaker 1: standard magnet staying perfectly still next to wire, you don't
Speaker 1: get the electricity to flow that way. And that is
Speaker 1: a very important aspect to memory storage as well. And
Speaker 1: that's our lesson on the physics of magnets. Without diving
Speaker 1: too deeply into quantum mechanics, I think we're ready to
Speaker 1: talk about our use of magnets with electronics. But first
Speaker 1: let's take a quick break to thank our sponsor. All right,
Speaker 1: we're back, and we just learned how magnets work in general,
Speaker 1: But when did we figure out they could be useful
Speaker 1: for storing information? So I'm gonna skip over all the
Speaker 1: historic uses of magnets leading up to data storage because
Speaker 1: I cannot spend another hour talking about compasses, or ironically,
Speaker 1: i'll lose Dylan here in the studio. So in the
Speaker 1: late nineteenth century we saw a boom in innovation that
Speaker 1: was mid to late nineteenth century was a crazy time
Speaker 1: in the world really for inventors discovering not just fundamental
Speaker 1: principles of science, but how to apply them in technology.
Speaker 1: I'm talking about stuff like Samuel Moore successfully sending an
Speaker 1: electrical signal that could be decoded into communication, all the
Speaker 1: way up to Alexander Graham Bell showing that electricity could
Speaker 1: also be used to carry audio signals and then be
Speaker 1: converted from electricity back into audio signals. That really got
Speaker 1: things moving. And over at Thomas Edison's Menlo Park, a
Speaker 1: guy named Oberlin Smith got a gander at a cylinder
Speaker 1: phonograph and got some interesting ideas. So first let's talk
Speaker 1: about this cylinder phonograph. It would record sound by transforming
Speaker 1: audio waves into electrical signals. That would then cause a
Speaker 1: needle to etch grooves into a wax cylinder. So you've
Speaker 1: got this wax cylinder. It would slowly spin, a needle
Speaker 1: would be dragged across it, and as sound came in,
Speaker 1: it would cause the needle to wiggle around and that
Speaker 1: should cause variations in the etching on the wax cylinder itself. Now,
Speaker 1: when you took that cylinder out and you put it
Speaker 1: in another phonograph and you placed a needle on it,
Speaker 1: uh within the groove and he started to earn the
Speaker 1: thing the cylinder, the needle would start to shake because
Speaker 1: it's following the groove that was made by the previous recording. Essentially,
Speaker 1: that whole process would be reversed. The shaky needle would
Speaker 1: generate an electrical signal which would then go to a
Speaker 1: essentially a speaker a diaphragm and cause it to vibrate
Speaker 1: and that would generate the sound. So you would get
Speaker 1: a replica of the sound you made when you were
Speaker 1: speaking into the wax cylinder phonograph. Now, Oberlin Smith wondered
Speaker 1: if he might be able to do the same thing,
Speaker 1: only instead of using a wax cylinder, he would record
Speaker 1: sound onto magnetic wire, not ape, not a disk, but
Speaker 1: an actual length of wire using magnetism. Now, he was
Speaker 1: not successful in this attempt, but he published his ideas
Speaker 1: in a journal called Electrical World in eight and ten
Speaker 1: years later a Dutch inventor inventor named Valdemar Poulson gave
Speaker 1: it another go. He began a working magnet recorder. He
Speaker 1: started building it. He called it the telegraphone Poulson, and
Speaker 1: he filed a patent for this invention in eighteen nine.
Speaker 1: So one year after he started working on it, he
Speaker 1: showed it off at the nineteen hundred Paris Exhibition. So
Speaker 1: how did it work? What exactly was it doing? How
Speaker 1: was it preserving this audio information in a magnetic format
Speaker 1: so that it could be played back? Well? Paulson knew
Speaker 1: that he needed a magnetically hard material. If you remember
Speaker 1: what I was talking about before the break, that's a
Speaker 1: material that we're retain its magnetic moment indefinitely. It may
Speaker 1: very gradually revert back to its original status, but it
Speaker 1: will hold it over a great deal of time. And
Speaker 1: if you want to record data for later retrieval, obviously
Speaker 1: you want to make sure that that data remains intact.
Speaker 1: Otherwise you have a self destructing or at least a
Speaker 1: self erasing message on your hands. So Poulson had to
Speaker 1: experiment with various factors to make certain he could record
Speaker 1: anything to the medium. To begin with, if the medium
Speaker 1: has a coercivity factor that's very high, that means you
Speaker 1: have to use stronger magnetic fields to affect it. I'm
Speaker 1: always talk about magnetic fields. Now I'm thinking about the
Speaker 1: Book of Love. It's great song by a group called
Speaker 1: the Magnetic Fields. Back back to this. So you have
Speaker 1: to have a really strong magnetic field in order to
Speaker 1: affect that material, and uh, that can be difficult. It
Speaker 1: can start to eat in on your efficiency. And you
Speaker 1: need the magnetic information to be distinct enough so that
Speaker 1: you could get a would replay signal. And uh, you know,
Speaker 1: when you're reading the material back later, you want to
Speaker 1: make sure you can actually hear what was recorded and
Speaker 1: not just get some sort of muffled you know, simulation
Speaker 1: of the of the sounds you made. So to record
Speaker 1: information onto a wire, you first need a recording head.
Speaker 1: You need something that's going to generate a magnetic flux
Speaker 1: that can affect the medium you're using the wire in
Speaker 1: this case. This, by the way, is also true for
Speaker 1: other methods of magnetic storage, including cassette tapes, VHS tapes,
Speaker 1: floppy disks, and some hard drives. When I say some
Speaker 1: hard drives, I mean magnetic hard drives. Obviously there solid
Speaker 1: state hard drives that are not affected in this way.
Speaker 1: They don't use that that technology, they are not part
Speaker 1: of this discussion. So the recording head is a transducer,
Speaker 1: and basically a transducer is something that converts some physical
Speaker 1: quantity into an electrical signal, or as the reverse, So
Speaker 1: you might have a transducer that can measure pressure like
Speaker 1: air pressure and change that into an electrical signal. That's
Speaker 1: a transducer. But in this case we're talking about things
Speaker 1: like a microphone a transducer, and a microphone converts pressure
Speaker 1: from sound waves into electrical signals. With recording devices, you
Speaker 1: can use one transducer to pull double duty one of them.
Speaker 1: It can act as both a recording head when recording,
Speaker 1: so it's it's actually writing something to the storage medium,
Speaker 1: or it could be a read head when playing a
Speaker 1: signal back. It's reading the signal and then converting it
Speaker 1: back into whatever it was originally before it was stored
Speaker 1: in that format. Now these days, most recording devices still
Speaker 1: use that are still using magnetic storage, have a dedicated
Speaker 1: recording head and a dedicated read head so that each
Speaker 1: transducer can be optimized for its respective role. You don't
Speaker 1: see a whole lot of them where it's doing both things. Uh.
Speaker 1: Some very cheap electronics, probably because then you don't have
Speaker 1: to have as many components in It makes it less
Speaker 1: expensive to produce. Now, the right head's job, or the
Speaker 1: recording head if you prefer, is to convert electric current
Speaker 1: into a magnetic field. But you remember what we said
Speaker 1: about electro magnets, that's pretty easy to do. The field
Speaker 1: it generates needs to be strong enough to affect the
Speaker 1: storage medium, the wire, but also it has to fall
Speaker 1: off quickly as you move away from the recording head.
Speaker 1: In other words, you don't want the effect to be
Speaker 1: widespread in area, or else you're going to end up
Speaker 1: affecting way too much wire at once. You'll end up
Speaker 1: with having to use way more wire to record very
Speaker 1: short sounds. In this case, and not only is that inefficient,
Speaker 1: but you'd also run the risk of writing over stuff
Speaker 1: you've just recorded. Let's say that you're writing something to wire.
Speaker 1: If the magnetic field is wide enough so that it's
Speaker 1: constantly overlapping what you just corded, then all you're really
Speaker 1: doing is muddling your recording with every successive sound. So
Speaker 1: a coil of wire creates the magnetic field when electricity
Speaker 1: runs through it. This wire is coiled around a soft
Speaker 1: magnetic material. Remember those are the kinds of magnetic materials
Speaker 1: that are easy to influence. But then we'll go back
Speaker 1: to their natural state shortly after the magnetic field they've
Speaker 1: been exposed to has gone away. This creates what we
Speaker 1: call a magnetic flux, and it concentrates at the tip
Speaker 1: of the soft magnetic material that's the core of this coil.
Speaker 1: A common design for early recording heads was a ring
Speaker 1: that had a small gap cut into it, and then
Speaker 1: you would wrap the wire around the inside of this ring,
Speaker 1: like you know around the ring. So imagine just a
Speaker 1: regular ring. You cut a little gap at one end.
Speaker 1: On the other end, you've wrapped this this coil of wire,
Speaker 1: and you run electricity through it. Turns the ring into
Speaker 1: a magnet, but the gap creates a difference in this
Speaker 1: magnetic field. The soft material, the soft magnetic material, conducts
Speaker 1: magnetic flux easily and the gap doesn't. This causes the
Speaker 1: magnetic flux to do something we call fringing. It fringes.
Speaker 1: A fringe field is a bit tricky to explain, but
Speaker 1: it's easier to understand if you imagine a horseshoe magnet.
Speaker 1: So the two ends of the horseshoe are the two poles,
Speaker 1: the north pole and the south pole. The fringe field
Speaker 1: is the magnetic field that extends outside the space between
Speaker 1: the two poles. That would be a fringe field. Now,
Speaker 1: that fringe field is what the right head uses to
Speaker 1: actually record information onto the magnetic medium. Now, with sound,
Speaker 1: we're talking about an analog approach, meaning you'd find a
Speaker 1: smooth variability in the medium. You would create that by
Speaker 1: varying the magnetic flux in subtle ways. The record warding
Speaker 1: head adjust the magnetic flux by varying the current running
Speaker 1: through the head and the recording medium thus has a
Speaker 1: variability in the magnetic flux recorded within the wire itself.
Speaker 1: The wire represents a sort of copy of the flux.
Speaker 1: If you were to run the wire back. So let's
Speaker 1: say you've got the red head. The transducer acts as
Speaker 1: a red head, and you run the wire next to
Speaker 1: it uh sequentially, so you're just spinning one reel pulling
Speaker 1: wire across so that this red head is very close
Speaker 1: to it. That would create a varying magnetic field across
Speaker 1: the gap in the red head, and that then would
Speaker 1: create a varying magnetic field in the core of the
Speaker 1: red head, which would induce a current to flow through
Speaker 1: the coil of wire, which then could be sent to
Speaker 1: an amplifier. The varying electric electrical signal goes to a
Speaker 1: transducer such as speakers, and then it can play back
Speaker 1: the sound. Now, those old wire recorders moved at a
Speaker 1: pretty good clip. A post war wire recorders would play
Speaker 1: back wire at about twenty four inches per second, so
Speaker 1: two ft a wire per second. That's about sixty one
Speaker 1: per second for you folks on the metric system, if
Speaker 1: you wanted to record an hour's worth of audio, you
Speaker 1: would need seven thousand, two hundred feet of wire or
Speaker 1: about two thousand one of wire, and you could only
Speaker 1: record along one direction of the wire. So if you
Speaker 1: want to listen to it again. You don't have to
Speaker 1: wind all the wire back up into a reel and
Speaker 1: then play it out across a reed head all over again.
Speaker 1: Most of these early ones were hand cranked too, so
Speaker 1: you would get variability on the sound quality as it
Speaker 1: was played back, plus when you were recording, so it
Speaker 1: took a steady hand to create a decent recording and
Speaker 1: a decent replication. And if you wanted to rerecord over it.
Speaker 1: Let's say that you've you know, you recorded an hour
Speaker 1: of someone catterwauling, and then you're like, well, that wasn't
Speaker 1: really worth it. I would love to use this wire
Speaker 1: to record something else. You would first have to run
Speaker 1: that wire by a strong permanent magnet, and that would
Speaker 1: effectively erase the stuff that was on it before, because
Speaker 1: the strong permanent magnet would cause all those uh, those
Speaker 1: those magnet magnetic domains inside the wire to realign to
Speaker 1: the permanent magnets magnetic field. It essentially erases all the variability,
Speaker 1: all the flux that was copied there before and turns
Speaker 1: it back into a uniform medium which you then could
Speaker 1: run through and record stuff on again the same thing.
Speaker 1: By the way, it's true for lots of other magnetic
Speaker 1: storage media. Now, eventually Poulson began to work with other
Speaker 1: types of magnetic media, and a big breakthrough came with
Speaker 1: the invention of plastic. I say the invention of I
Speaker 1: really mean the mass production of plastic has been around
Speaker 1: for a pretty a long time, but I'm talking about
Speaker 1: when we really started producing it on a mass scale.
Speaker 1: So you can use plastic film coated with a ferro
Speaker 1: magnetic powder. This is how cassette tapes, VHS tapes, even
Speaker 1: floppy disks work. You can make a cheap recording medium
Speaker 1: this way. Uh, the invention of the cassette tape itself
Speaker 1: was another big jump because engineers figured out how you
Speaker 1: could double the amount of material you could record on
Speaker 1: a tape if you just recorded on half of it
Speaker 1: at a time. Now, this is a little tricky to
Speaker 1: explain without the use of visual aids, but I'll try
Speaker 1: and give it a shot. So imagine that you've got
Speaker 1: a length of flat ribbon in front of you. You
Speaker 1: might think of cassette that cassette recorders are actually putting
Speaker 1: information on both sides of the ribbon, but that's not
Speaker 1: what is happening. All the information for side A and
Speaker 1: side b are on one side of that ribbon, but
Speaker 1: they are one hundred and eighty degrees opposite each other,
Speaker 1: side by side. So you lay out the ribbons so
Speaker 1: it's horizontal in relation to you. You're looking at a
Speaker 1: horizontal strip of ribbon. Imagine a line going down the
Speaker 1: middle of that ribbon horizontally. The top half of the
Speaker 1: ribbon is one side of the cassette and the bottom
Speaker 1: half is the other side of the cassette. So when
Speaker 1: you put a cassette into a cassette player, the reed
Speaker 1: head is positioned over just one half of that tape
Speaker 1: and it reads what's off of that. When you flip
Speaker 1: the cassette over, then the side of the tape that's
Speaker 1: running across the reed head is the opposite of of that.
Speaker 1: You know, it's the bottom of the ribbon as opposed
Speaker 1: to the top of the ribbon, and that's all you're
Speaker 1: able to listen to side b uh. So that's kind
Speaker 1: of cool, I thought. Now, next, I'm gonna talk specifically
Speaker 1: about using magnetism to store information for a digital computer,
Speaker 1: which is a little bit different from what I've been
Speaker 1: chatting about so far. But first, let's take another quick
Speaker 1: break to thank our sponsor. All right, So in the
Speaker 1: last section I talked about how magnetic recording can create
Speaker 1: a variable magnetic flux for analog playback. But what about computers.
Speaker 1: Computers rely on binary language, not analog. It's not a variability,
Speaker 1: it's a collection of zeros and ones. You have to
Speaker 1: describe computer information in this format as either a zero
Speaker 1: or one. Ultimately, when you get down to it, every
Speaker 1: computer language out there, once you get down to the
Speaker 1: very basics, ends up being translated into zeros and ones
Speaker 1: because computers just don't deal with these variable fields. So
Speaker 1: how do you get it to do that? So, while
Speaker 1: the format is more or less obsolete, I'm gonna talk
Speaker 1: about floppy disks for a bit, and that's because there
Speaker 1: are a lot of parallels between floppy disks and cassette tapes,
Speaker 1: which I talked about in the last section. Floppy disks,
Speaker 1: by the way, used to come in several sizes. When
Speaker 1: I first started using computers, the standard size in the
Speaker 1: US was the five and a quarter inch disc. There
Speaker 1: were larger discs that came before that, but the first
Speaker 1: ones I ever used were five and a quarter inch.
Speaker 1: A lot of people thought they were called floppy disks.
Speaker 1: Because the outer sheath of the disc itself was flexible.
Speaker 1: Some people even thought you could fold them up and
Speaker 1: put them in your pocket, which technically I guess you
Speaker 1: could do, but you wouldn't be able to use them
Speaker 1: later because you mangle the disk inside and it would
Speaker 1: no longer spend properly inside a computer. So don't do that.
Speaker 1: Later on came the three and a half inch discs,
Speaker 1: and these had a hard plastic casing, but they were
Speaker 1: still floppy disks because the disk inside, the actual medium
Speaker 1: upon which information was stored, was still this flexible material.
Speaker 1: A lot of folks thought that these three and a
Speaker 1: half inch discs were actually hard disks. They said, you know,
Speaker 1: the floppy disks were the five and a quarter three
Speaker 1: and a half Because the plastic it is sturdy, that's
Speaker 1: a hard disk. No, that's not a hard disk. But anyway,
Speaker 1: that's all ancient history, and you guys probably don't even
Speaker 1: understand what I'm talking about. Get off my lawn, all right.
Speaker 1: Inside the outer covering of these discs was the actual
Speaker 1: disc itself. We call the floppy disks that, but they're
Speaker 1: not disc shaped. If you were to show someone a
Speaker 1: floppy disk and they had absolutely no context for it.
Speaker 1: They knew what the word disc meant. They take one
Speaker 1: look at and say, why the heck do you call
Speaker 1: it a disc. It's because on the inside there is
Speaker 1: a disc of material, and it is essentially a plastic
Speaker 1: base that's coated with ferro magnetic materials. And the advantage
Speaker 1: of this is that if you apply a magnetic field
Speaker 1: to it, it would record that information permanently, or at
Speaker 1: least until you erased it and wrote over it, or
Speaker 1: if you encountered a really strong magnetic field, and it
Speaker 1: was a really fast way to record a lot of information.
Speaker 1: So disks are organized into concentric rings. You can kind
Speaker 1: of think of an old vinyl album in the same
Speaker 1: way how the grooves slowly move inward on the um
Speaker 1: on the disc, But in this case their actual concentric
Speaker 1: rings of information, not not just one line that slowly,
Speaker 1: you know, swirls inward towards the center. So when a
Speaker 1: computer is reading information back, it can it can reference
Speaker 1: some information at the at the front of the disc
Speaker 1: and learn exactly where a file is located, and it
Speaker 1: can then position the read right head directly over the
Speaker 1: appropriate part of the disc, rather than having to go
Speaker 1: through the whole thing sequentially. So with the cassette tape,
Speaker 1: if you want to listen to a specific song, you
Speaker 1: have to wait. You mean, you can use fast forward
Speaker 1: to speed things up, but you can't jump straight to
Speaker 1: the track you want to hear, unlike you could with say,
Speaker 1: compact disc. Well, in this way, a flop disc is
Speaker 1: more like a compact disc in that a computer can
Speaker 1: understand exactly where the file is stored within those concentric
Speaker 1: rings and go straight there. In other ways, it is
Speaker 1: very different from a compact disc, but in that specific
Speaker 1: way it is similar. Now in other words, it's kind
Speaker 1: of like lifting a record player's needle off of one
Speaker 1: groove and skipping ahead to a specific song on an album,
Speaker 1: lowering the needle and then playing it, and thank goodness
Speaker 1: record players are coming back. So that you guys know
Speaker 1: what I'm talking about when I say these things. This,
Speaker 1: by the way, is a type of direct access storage,
Speaker 1: meaning the computer can get direct access to that information
Speaker 1: in a very short amount of time. When writing to
Speaker 1: a disc, first the drive will use in a race coil,
Speaker 1: and this essentially just clears a section of the storage
Speaker 1: medium for writing. So it's it's kind of like exposing
Speaker 1: that steel wired to a permanent magnet. It's that same principle.
Speaker 1: You want a clean slate to write upon, and typically
Speaker 1: this clean slate is a bit wider than the actual
Speaker 1: right section you're going to be working on. You want
Speaker 1: the area that is a clean slate to be larger
Speaker 1: so that you have a buffer zone at either end,
Speaker 1: and that way it keeps adjacent files from interfering with
Speaker 1: each other. If you were writing information to that part
Speaker 1: of the disc and it went over that area, you
Speaker 1: would start writing on top of some other file and
Speaker 1: then the storage wouldn't work at all. So the right
Speaker 1: head puts data on the disk drive by applying one
Speaker 1: of two magnetic fields to the tape. It either aligns
Speaker 1: the magnetic material as north south or south north. That
Speaker 1: means it's either a zero or a one. Like so
Speaker 1: imagine that north south magnetization represents a zero and ou
Speaker 1: north represents a one. The right head can then go
Speaker 1: through this disc very very quickly, applying these magnetic fields
Speaker 1: one after the other, maybe several North south in a
Speaker 1: row followed by a south north or whatever, and it
Speaker 1: is recorded on the disc itself, and when you read
Speaker 1: it back then you know by looking at the code,
Speaker 1: Oh these are you know, three zeros in a row
Speaker 1: and then a one. It replicates those zeros and ones
Speaker 1: that were recorded to the storage medium. This, in a
Speaker 1: way is much more simple than a variable magnetic flux
Speaker 1: because you only have to have two magnetic states. You
Speaker 1: just have to have something that represents a zero and
Speaker 1: something that represents a one. No other values are accepted,
Speaker 1: so you just have to have those two basic modes,
Speaker 1: and the same basic principles apply to other computer magnetic storage.
Speaker 1: Magnetic hard drives use a very similar approach to the
Speaker 1: ones I described for floppy drives. And you probably heard
Speaker 1: that it's a bad idea to expose computers to strong
Speaker 1: magnetic fields, and the big reason for this is that
Speaker 1: magnetic storage. If you bring a strong permanent magnet close
Speaker 1: enough to magnetic storage media, you'll erase the data that's
Speaker 1: stored there. That includes data that's on a hard drive
Speaker 1: if it's a magnetic drive, right, if it's a solid
Speaker 1: state drive, it's a different story. Or if you were
Speaker 1: to take a strong permanent magnet and threatening someone by
Speaker 1: by holding a compact disc with all their photos on it,
Speaker 1: and you're saying if you come any closer, I'm going
Speaker 1: to ruin your pictures by putting this magnet up to
Speaker 1: the c D. It won't work because the information stored
Speaker 1: on the CD is an optical format, not magnetic, and
Speaker 1: magnets aren't going to affect it at all, so you
Speaker 1: shouldn't be doing that anyway. It's kind of a jerk move,
Speaker 1: but it wouldn't work, is what I'm getting at. So
Speaker 1: in future episodes I plan on exploring stuff like optical
Speaker 1: storage and how that works, how is it similar to
Speaker 1: and different from magnetic storage? And also solid state drives,
Speaker 1: which are you know, pretty much the standard and a
Speaker 1: lot of different computers these days, which have incredible advantages
Speaker 1: in how quiet they are and how fast they are,
Speaker 1: but they tend to be a lot more expensive than
Speaker 1: your old style magnetic drives. I'll talk about those in
Speaker 1: future episodes too, And if you guys have any questions
Speaker 1: about the stuff I mentioned here, feel free to send
Speaker 1: me an email. My address is tech stuff at how
Speaker 1: stuff Works dot com, or you can always drop me
Speaker 1: a line on Facebook or Twitter. The handle of both
Speaker 1: of those is text stuff H s W. And I
Speaker 1: will talk to you again really see for more on
Speaker 1: this and thousands of other topics. Is it how stuff works?
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