Re: SAGE program at 1:20 - I worked on ASUPT - Advanced Simulator for Undergraduate Pilot Training - which the US Air Force brought on line in 1973. It was the first flight simulator to have a computer generated visual display. The computers (there were three) had core memory, mag tapes, and a disk drive with a stack of nine interchangeable 12 inch metal plates. It was programmed on cards in a combination of FORTRAN and the dialect of assembly for that machine. I don't recall the exact number of cards in the total load, but I seem to remember it was more than the 63500 you quoted for SAGE. For what it's worth, the research we did on that machine to find out the best way to use simulators for pilot training led directly to the simulators used by airlines today to train their pilots and run annual emergency procedure check rides (think practicing engine out landings).
Hey guys, you know what’s great - repurposing obsolete technology. We here at Crash Course HQ like floppy disk coasters so much, that we thought you might like some too. So we made a batch of limited edition Crash Course Comp Sci Floppy Disk Coasters!* Limited because, well, floppy disks are kinda tough to come by these days. So if you too want to say goodbye to cup rings and hello to low-density storage media follow the preorder link here! store.dftba.com/products/computer-science-coasters *some assembly required
Guys just remember that these crash course videos are intended for students, people who generally weren't around for floppy disks. They still probably know what a floppy disk is though. Of course you don't have to be watching these for test purposes. They're fun to watch on their own.
"Unpunching a hole is hard", but far from impossible. My university was still using punch cards in 1980 (replaced with terminals the following year) and the lines for the punch machines would get silly near course deadlines. So I had a bag of holes collected from the punch machines (on days they weren't so busy), a razor and one reference card with all the characters punched in it. Adding a few holes and eliminating a few from a card could be done in a minute instead of waiting hours in line for a free machine.
the last 8 columns of the punch card used to number the cards in order. So, if that breeze came a long the, card puncher could be used to sort them back into the right order. They did have some smarts back then. love your stuff.
In the early 2000s I worked in a data center that made good money by using 2 tape drives to move cold storage reels to DAT. I have lived through way too many memory formats. Your coasters look way too familiar! Carrie, great series and episode!
Curly G Cradle Rock I live in a third world country and I only stored word documents for only one use. Also a CD burner wasn't that common in the day. So floppy disk was the best options for my needs
Sounds about the same as when I was last regularly using them to transfer files. I have even used them in the past few years for plop boot manger so I could boot old PCs off a USB stick.
I think they use a special type of transistor that somehow get stuck so when you turn off your computer inside the SSD there's still electricity in there
en.wikipedia.org/wiki/Flash_memory#NAND_flash To greatly oversimplify, they use the classic gates we saw earlier in this series, but with a type of transistor that has resistive material around it, holding the charge "in place" unless a stronger charge overwrites it.
Solid state memory (e.g. flash memory) uses a floating gate transistor to trap electrons. There are lots of videos on youtube how it exactly works (it's technical and requires "quantum tunneling". But it's non-volatile because once the electrons are trapped, you don't need to supply power to retain the memory.
I remember when you could buy floppy discs for a dollar with programs you could try before you might want to buy the original. The little cards on Star Trek that Spock used was a prediction of floppy discs.
I suppose 10 or 20 years from now, kids will still be learning from these awesome Computer Science videos and it will feel more like the floppy disk really was an ancient fossil.
Something that should be noted about SSDs is that they're different from normal ICs in that the storage process involves essentially pushing electrons with really high force into and out of materials with really high resistance. The resulting electrostatic fields turn field effect transistors on or off, without needing moving electrons.
I've used IBM mainframe DASD since the mid 1980s as a programmer and knew how it worked in theory but never seen the read write heads actually working on the stacks of disks before. I remember seeing laser disks on the BBC TV show tomorrow's world when I was a kid in the 1970s.
She Looks like a Real Sheldon's Sister! British | Big Bang Theory| I was working on ServiceNOW Storage discovery and I landed up here. Lots of hard work she's done. God Bless and keep making great videos!
Floppy disks old? I remember Commodore 64 and games recorded on cassette tapes! It makes no wonder why I don't remember C64 having any RPG or RTS games, considering that C64 had no hard drive (all it had was RAM and ROM memory) to save game record on it.
I think Flash and SSD weren't explained in this episode. I've heard they work with trapped electrons, but it would be interesting to know in more detail.
The use of "memory" and "storage" in the video is the most popular, but is not universal. Von Neumann liked to use biological terms like "memory" and "organs" when describing computers but many people preferred "storage" and "subsystems" to avoid misleading analogies. IBM often (but not always) used "storage" to mean the same things that other companies called "memory".
My first programs and data were stored on punch cards. The saving grace of dropping a stack of cards were good old rubber bands - two if you were especially paranoid. I've seen people drop large stacks of loose cards and cry and cry....
I heard that libraries in programming came originally from the era of punch cards with people putting together useful pieces of code into a repository where computer scientists at their university could check out that block of punch cards to use in their program.
I love how, along with the usual students, there's a lot of us folks in the comments who were learning about computers in the 70s and 80s. Next episode on cache invalidation? ;-)
I only have floppy disks in my house because my dad was interested in computers when he was younger. I don't remember ever actually using one though. You mentioned that SSDs use the same technology that we already talked about, but wasn't that volatile? Can you please elaborate how flash memory works and why it's non-volatile?
Wow! This video is very educational and explained amazingly well!.. there were other information i dint find in other videos about history of memory but found in yours.. Thanks a lot!!
My first computer (a ten-year0old Tandy TRS-80) used a Compact Cassette instead of a disk drive. It was finicky, you had to adjust the gain/volume just so to make the computer read it. Apparently a bit later there was a little-used system to use VHS tapes for cheap tape backup, but it was even more finicky because of all the extra stuff going on in a VCR with the helical scan head and whatnot. Googling trying to find it, it seems the Arduino crowd are still toying with the idea, just because of the silliness of it -- I mean, you could put a full Arduino system with a multiple-terabyte SSD in a VHS tape's shell. (Which actually sounds like a fun project, I've seen Arduino/RasPi-based NES emulators in an NES cart, why not put the video-playing machine in a VHS cassette?)
I remember when XP required me to install a SATA driver via a floppy (and no other way!!!) just so I could actually use my C drive. After my floppy drive died, it was easier to just install Vista which had all that built in.
several times in the video (i posted this after hearing 6:47) where she said "-bytes" when she should have said "-bits" DIVIDE BY 8 OR END WITH BITS INSTEAD OF BYTES
I remember trying to save word docs with loads of clip art on a floppy disk but was so confused as to why I could never save even one document while my mum was able to save lots of word docs with no pictures 😂 Eventually it clicked
I have a question . Why there are so many short terms memories available ? Why not only one ? Why so many like Ragisters , Cache and Ram . Need your help and waiting for your reply 🙄
Thank you for this nice videos playlist ! I am enjoyed and interested with every single episode. About this one, I can't find the episode where you spoke about solid state memory ? This is not #15. Which one is it ?? Thanks
Not to be pedantic, but I computed the size of the "largest punch card based application" to be approx 7,15 MB and not 5MB as reported in the video. Did I calculate it wrong?
Insane how difficult the climb to modernity has been in all aspects.
Re: SAGE program at 1:20 - I worked on ASUPT - Advanced Simulator for Undergraduate Pilot Training - which the US Air Force brought on line in 1973. It was the first flight simulator to have a computer generated visual display. The computers (there were three) had core memory, mag tapes, and a disk drive with a stack of nine interchangeable 12 inch metal plates. It was programmed on cards in a combination of FORTRAN and the dialect of assembly for that machine. I don't recall the exact number of cards in the total load, but I seem to remember it was more than the 63500 you quoted for SAGE.
For what it's worth, the research we did on that machine to find out the best way to use simulators for pilot training led directly to the simulators used by airlines today to train their pilots and run annual emergency procedure check rides (think practicing engine out landings).
I learned to program in FORTRAN on punch cards. I think Fred Flintstone was attending the same school.
Remember when there were no wheels?
That was the best, most witty and smart, patreon showtout I’ve ever heard! 😆
"you may recognise this as a save icon but these were once physical objects" OH COME ON! When did I become prehistoric?! :)
James Pilcher I never saw a floppy disk in real life '-' I'm 16 btw
Enoque Sousa, I occasionally used them, and I'm 18.
Enoque Sousa I don't like you now...
I've only seen floppy disks in videos and as a save icon. I'm 16
James Pilcher i was born in the 90's and i also remember seeing physical floppy disks, although they were slowly becoming less common
You know you're old when you hear a kid say, "oh you 3D printed the save icon" lol. Whoever was the first person to say that deserves a high five.
I once overheard a little boy calling the floppy disk icon the "Transformer save button", so yep.....
Hey guys, you know what’s great - repurposing obsolete technology. We here at Crash Course HQ like floppy disk coasters so much, that we thought you might like some too. So we made a batch of limited edition Crash Course Comp Sci Floppy Disk Coasters!* Limited because, well, floppy disks are kinda tough to come by these days. So if you too want to say goodbye to cup rings and hello to low-density storage media follow the preorder link here! store.dftba.com/products/computer-science-coasters
*some assembly required
Veterinary!!! I know you see me -_- !!!
If floppy disks are obsolete, then I'm an old man, so logically, floppy disks cannot be obsolete. Logic!
can I use the floppy coaster for recording data?
I was hoping you were going to say you would take all our old floppies. I have boxes of them.
Need a donation of a few hundred more floppy disks? And/or can I download and/or buy just the labels to apply to my own floppies?
Carrie, you talked about Floppy disks like they were fossils. I suddenly feel very very old.
Kellie Fay it puts me in mind of Back To The Future II - "you mean you have to use your hands?! It's like a baby's toy!"
And she didn't even have an 8" or 5.25". Those REALLY flopped!
Right? I don't recognize them from the save icon, I recognize them from HAVING USED THEM FOR STUFF
Rev. Dave Moorman I was about to say "raise your hands if you used the 5.25 floppies. 😄
I used them to install Chip's Challenge in Windows 3.1... Oh boy my age....
Guys just remember that these crash course videos are intended for students, people who generally weren't around for floppy disks. They still probably know what a floppy disk is though. Of course you don't have to be watching these for test purposes. They're fun to watch on their own.
"Unpunching a hole is hard", but far from impossible. My university was still using punch cards in 1980 (replaced with terminals the following year) and the lines for the punch machines would get silly near course deadlines. So I had a bag of holes collected from the punch machines (on days they weren't so busy), a razor and one reference card with all the characters punched in it. Adding a few holes and eliminating a few from a card could be done in a minute instead of waiting hours in line for a free machine.
the last 8 columns of the punch card used to number the cards in order. So, if that breeze came a long the, card puncher could be used to sort them back into the right order. They did have some smarts back then. love your stuff.
Your right. The video even briefly showed a sorter working. Conventionally, the sequence id number was in the right-most columns.
Nonetheless, manually re-sorting a few thousand punch cards is kind of annoying.
If anything, it sounds like they had more smarts back then than we do now.
In the early 2000s I worked in a data center that made good money by using 2 tape drives to move cold storage reels to DAT.
I have lived through way too many memory formats. Your coasters look way too familiar! Carrie, great series and episode!
This is really helpful for Computer Science students!
TRUE!
Really helpful! ;D
And random photographers who wondered their pictures were actually stored in tiny little bits of seeming magic!
I, uh, hope it is. That's the point.
Yeah if they want to know how it came around, there is little no no information on how modern ram works
Currently studying computer science. This blows my mind!
I felt so old when you tslked about floppy disk not existing anymore. I mean, It wasn't that long ago. I think I used them 12 years ago.
I'm really glad I didn't need to use floppy disks in 2005. Jesus dude, CDRW drives were $20 even back then, CDs were a dollar.
Curly G Cradle Rock I live in a third world country and I only stored word documents for only one use. Also a CD burner wasn't that common in the day. So floppy disk was the best options for my needs
yea.. its a bit dum. some stores you can still buy them, and they are still used in many professional equipment
Sounds about the same as when I was last regularly using them to transfer files. I have even used them in the past few years for plop boot manger so I could boot old PCs off a USB stick.
@@owlredshift I already got no CDROM by 2006)digital only
You are a great tutor, Carrie. Thanks for making this tutorial.
Thanks for another great episode! The mix of history and technical detail is just wonderful. Keep them coming please.
CrashCourse ROCKS! Hope our videos will reach your quality someday :)
:D
Oh boy, back when you ask a coworker if they had a _"Floppy disk"_ or a _"Hard disk"_ .
I have a hard disk ( ͡° ͜ʖ ͡°)
I have an SSD. What does that mean?
First S stands for solid. Not sure if it supposed to be that way. You should check yourself bro
Ganaram Inukshuk solid state drive
Someone in this thread doesn't get the joke.
*read in Grandpa voice* Back in my day we used to use compact disks to store memory! We did things right back then. Ahhhh, I miss the old days.
I've a test on digital systems design on Friday. I love this lady!
This series needs more views, really well put together.
9kb is wrong, its around 1kb. ;) 5:00
But how are solid state storage technologies of today not volatile?
Yeah, I really wished they'd answer that.
Matthew Hoiland I would love an explanation for that, I understand cds and hdds and ram easily enough, but ssds are still magic to me.
I think they use a special type of transistor that somehow get stuck so when you turn off your computer inside the SSD there's still electricity in there
en.wikipedia.org/wiki/Flash_memory#NAND_flash
To greatly oversimplify, they use the classic gates we saw earlier in this series, but with a type of transistor that has resistive material around it, holding the charge "in place" unless a stronger charge overwrites it.
Solid state memory (e.g. flash memory) uses a floating gate transistor to trap electrons. There are lots of videos on youtube how it exactly works (it's technical and requires "quantum tunneling".
But it's non-volatile because once the electrons are trapped, you don't need to supply power to retain the memory.
I remember when you could buy floppy discs for a dollar with programs you could try before you might want to buy the original. The little cards on Star Trek that Spock used was a prediction of floppy discs.
I was in college in the early 1980's and took a PL/I course. It was on punch cards - how archaic even then.
I work for IBM Storage and am really happy to see this episode! :D
I suppose 10 or 20 years from now, kids will still be learning from these awesome Computer Science videos and it will feel more like the floppy disk really was an ancient fossil.
Something that should be noted about SSDs is that they're different from normal ICs in that the storage process involves essentially pushing electrons with really high force into and out of materials with really high resistance. The resulting electrostatic fields turn field effect transistors on or off, without needing moving electrons.
I've used IBM mainframe DASD since the mid 1980s as a programmer and knew how it worked in theory but never seen the read write heads actually working on the stacks of disks before. I remember seeing laser disks on the BBC TV show tomorrow's world when I was a kid in the 1970s.
This series is the best. Carrie Anne you are amazing!
5:56 "If you have that kind of money to drop, did you know that CrashCourse is on Patreon? Wink wink-"
*Stop. I'm laughing too much.*
I have a lot of catching up to do in this series. Time to binge watch from square one ....
She Looks like a Real Sheldon's Sister! British | Big Bang Theory| I was working on ServiceNOW Storage discovery and I landed up here. Lots of hard work she's done. God Bless and keep making great videos!
Floppy disks old? I remember Commodore 64 and games recorded on cassette tapes! It makes no wonder why I don't remember C64 having any RPG or RTS games, considering that C64 had no hard drive (all it had was RAM and ROM memory) to save game record on it.
I think Flash and SSD weren't explained in this episode. I've heard they work with trapped electrons, but it would be interesting to know in more detail.
+1
"If you have that much money to drop, did you know that CrashCourse is on patreon" lol that got me.
I remember the times we used floppy disks.
Damn, I feel old now.
The use of "memory" and "storage" in the video is the most popular, but is not universal. Von Neumann liked to use biological terms like "memory" and "organs" when describing computers but many people preferred "storage" and "subsystems" to avoid misleading analogies. IBM often (but not always) used "storage" to mean the same things that other companies called "memory".
My first programs and data were stored on punch cards. The saving grace of dropping a stack of cards were good old rubber bands - two if you were especially paranoid. I've seen people drop large stacks of loose cards and cry and cry....
It's really interesting to me thapt the development of magnetic memory paralleled that of early audio recording from drums to disks.
Floppys were definitely used after the mid 90s. I remember using them in school and at home when I was a kid back in the late 90s/early 2000s
Carrie Anne Philbim, a computer genius and great tutor. Thanks. How I after this series you can teach us programming!
You should have touched on the people that make music with old floppy drives, That would have been fun.
Really good memory hierarchy pyramid chart 8:53
I heard that libraries in programming came originally from the era of punch cards with people putting together useful pieces of code into a repository where computer scientists at their university could check out that block of punch cards to use in their program.
You sound so passionate!!!
Don't forget: Disk is magnetic, Disc is optical. e.g. Floppy Disk, Compact Disc
Thank you so much, I will explain my students about that!
I love how, along with the usual students, there's a lot of us folks in the comments who were learning about computers in the 70s and 80s. Next episode on cache invalidation? ;-)
It would be a shame if someone where to sneeze in the room with all my punch cards.... luckily I actually use SSD
I only have floppy disks in my house because my dad was interested in computers when he was younger. I don't remember ever actually using one though.
You mentioned that SSDs use the same technology that we already talked about, but wasn't that volatile? Can you please elaborate how flash memory works and why it's non-volatile?
Lots of cool and neat stuff that lead us to where we are now in the information age. Thanks for the video!
oh H311 yes! just pre-ordered those floppies!
Wow! This video is very educational and explained amazingly well!.. there were other information i dint find in other videos about history of memory but found in yours.. Thanks a lot!!
Very good presentation
Great show. Wonderful host.
At around 4:55 you mention that 9216 bits is 9 kilobytes, it's 9 kilobits.
You're right it would be 9216÷8=1152 or just over one kilobyte
A fantastic watch!
The editing introduced a continuity error. There's a callback to the "one cent per bit" factoid at 9:28 but it isn't introduced until 10:53
Zip disks were not floppy! Zips were basically small removable hard disks. There were also higher-capacity floppy disks, but zips weren't one of them.
I worked with punch cards, and still I have nightmares of the punch machine spitting out cards in the air. Each batch job took us 9 hours to run.
I was a senior in high school in 2008, we still used floppy disk
4:48 : 9x1024 Bit = 9 kBit which is about 1,2 kByte
My first computer (a ten-year0old Tandy TRS-80) used a Compact Cassette instead of a disk drive. It was finicky, you had to adjust the gain/volume just so to make the computer read it. Apparently a bit later there was a little-used system to use VHS tapes for cheap tape backup, but it was even more finicky because of all the extra stuff going on in a VCR with the helical scan head and whatnot. Googling trying to find it, it seems the Arduino crowd are still toying with the idea, just because of the silliness of it -- I mean, you could put a full Arduino system with a multiple-terabyte SSD in a VHS tape's shell. (Which actually sounds like a fun project, I've seen Arduino/RasPi-based NES emulators in an NES cart, why not put the video-playing machine in a VHS cassette?)
I remember when XP required me to install a SATA driver via a floppy (and no other way!!!) just so I could actually use my C drive. After my floppy drive died, it was easier to just install Vista which had all that built in.
4:57 - 9 kiloBITs
I'm a bit disappointed that she didn't point out that we could recognize the magnetic drums as the "loading" LED in modern computers.
Surely she meant, "...around 9 kilobits." But more specifically, it would be 9 kibibits.
thanks C.A.!
several times in the video (i posted this after hearing 6:47) where she said "-bytes" when she should have said "-bits"
DIVIDE BY 8 OR END WITH BITS INSTEAD OF BYTES
7:38 finally, you did it correctly
11:00 Sure, the seek times may be slow by comparison, but the fastest consumer SSDs out there are about as fast in terms of bandwidth.
The title of this video should be " HISTORY OF COMPUTER MEMORY & STORAGE"
ANOTHER LEVEL OF ABSTRACTION
I first liked, then watched to see. Love you Anne...
You're awesome, great video! :D
i hope this channel continues to eternity
I remember trying to save word docs with loads of clip art on a floppy disk but was so confused as to why I could never save even one document while my mum was able to save lots of word docs with no pictures 😂 Eventually it clicked
Very useful
But aren't those acoustic delay lines power dependent? They were used for the same purpose as we use RAM today, right?
Optane Isn't Nearly as fast as RAM. As a matter of fact, a RAID 0 array of 2 optane m.2 drives. The distinsion is always big. RAM is also improving.
Fantastic episode!
Thanks
I have a question . Why there are so many short terms memories available ? Why not only one ? Why so many like Ragisters , Cache and Ram . Need your help and waiting for your reply 🙄
You guys should get your theme for this series played on Floppotron!
Comp sci am best crash course.
You forgot to mention Williams tube and Selectron tube!
Thank you for this nice videos playlist ! I am enjoyed and interested with every single episode. About this one, I can't find the episode where you spoke about solid state memory ? This is not #15. Which one is it ?? Thanks
Wow, even she called the intel SSD a harddrive @10:35
Love Crash Course. Thank you!
Not to be pedantic, but I computed the size of the "largest punch card based application" to be approx 7,15 MB and not 5MB as reported in the video. Did I calculate it wrong?
I tell ya you need to break for awhile after 5minute of video. The information surge my brain quickly filling the buffer
People can know about things after they’re stopped being produced
The disc HD is what slows computers down.
thank you so much for this video..it was of tremendous help
I feel superior to others for having a childhood that coincided with the tail-end of the floppy disk lifetime.
Damn, I totally have some old floppy disks and I need coasters.
Great video!
I play this when I can't sleep.
One time in my computer class, I got confused between Moore's Law and Murphy's Law