Files & File Systems: Crash Course Computer Science #20

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Today we’re going to look at how our computers read and interpret computer files. We’ll talk about how some popular file formats like txt, wave, and bitmap are encoded and decoded giving us pretty pictures and lifelike recordings from just strings of 1’s and 0’s, and we’ll discuss how our computers are able to keep all this data organized and readily accessible to users. You’ll notice in this episode that we’re starting to talk more about computer users, not programmers, foreshadowing where the series will be going in a few episodes.
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Опубликовано:

26 сен 2024

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Комментарии : 416

@Supermunch2000 7 лет назад

This crash course is one of the most delightful things to ever appear on the internet. Thank you Carrie Anne, Stan and everybody else involved.

@imaytag 7 лет назад

Every time I watch one of these videos I always imagine going back in time and showing it to an early computer scientist and seeing their reaction to how far we've come.

@imaytag 7 лет назад

Heh, yeah. But I meant going back to a time when the technology was still developing. And seeing their reaction for those times when Carrie Anne casually references the capabilities of modern computers.

@sauravligal5809 5 лет назад

evolution of computer is fast...

@nosuchthing8 5 лет назад

Yeah, but they would be shocked we still don't have human level ai.

@23trekkie 7 лет назад

Defragmentation was fun to watch... If you had angelic patience and nothing better to do. Before defragmentation - 25% fragmentation. 12 hours later - 24% fragmentation.

@samuelisaac2984 4 года назад

24 hours later: 26% fragmentation.

@Phantom-nb5li 4 года назад

It's great that the presenter doesn't shy away from "advanced" topics (in any of the videos in this course) - that provides something for every "level" (beginner / intermediate / advanced) of viewer. Great job with these videos !

@WiseWik 7 лет назад

Only 90's kids remember how fun it was to watch defrag.

@hopeg97 7 лет назад

Pajaat Or 00's kids with passed-down legacy hardware. I remember watching Windows XP defrag. I think I also remember Windows 7 defragging, but it wasn't nearly as fun. (born '97, so anything before 2002 is lost to childhood amnesia)

@JimPlaysGames 7 лет назад

You can always get third party defraggers with nice GUIs that show off the data juggling.

@huge_aubergine 7 лет назад

I wouldn't say it was fun. I was expecting my Windows to run smoothly after every defrag, but it never happened :(

@RomanKorostenskyi 7 лет назад

I'm 00's kid, and I remeber that defrag^^

@IIGrayfoxII 7 лет назад

The Windows 9x defrag utility was the best, all those little blocks. XP just had the stupid bar which didnt tell you much Windows vista and newer got rid of the animations with the claim it improves performance.

@PrivateYouTubeE 4 года назад

After so many years, I finally know defragmentation means and what it does. Thank you so much.

@Agen7P 7 лет назад

We're now up 20 Layers of abstraction.

@orion10x10 5 лет назад

l a y e r s

@Fcycfvyvvyvtfutg 5 лет назад

That’s not how it works...

@evanl5299 6 лет назад

I just read a full textbook chapter on this, but the way you described file systems made it so easy to understand! Thanks for this excellent, concise video. Great work!!

@somethingnew3338 Год назад

best explanation for file system. I saw around 10 videos till now. thanks and congrats

@sameerkumar1884 4 года назад

This video is really informative for knowing nitty gritty about file system specially "Block Storage"... It can also be used to understand about newly evolved Object storage...

@dixztube 2 года назад

This was pretty good! Read a couple chapters today in a Linux book covering storage partitions and file systems and this had some tidbits a fairly technical book left out. I’ve been developing for 5 years now and finally just now falling in love with computer science

@lorenz_codes 2 года назад

I feel like I struck gold with this series! Thanks for making these videos!

@djmontoro 7 лет назад

This is by far the Crash Course series from which I have learned more. Thanks, Excellent work!!!

@tylerblackstock6452 6 лет назад

Love this whole series, you make it easy to understand the flow of technological advancement

@TYKUHN2 6 лет назад

I can understand the simplification, but it is important to remember that many programs running under Unix/Linux do not care about extension and furthermore EXT4, a common Linux filesystem, does not experience fragmentation.

@TYKUHN2 6 лет назад

Peterolen very few programs (at least that I work with) care about the extension

@WoutiecomNL Год назад

Wow, my first time watching a video from your channel. As I am interested in File Systems I came across this video. You, Carrie, can explain it very clearly and your animations and sounds are pleasing on the eye ;)

@thecentalist3160 7 лет назад

YAY two of my favorite series uploaded on the same day.

@noemiej.marquis732 7 лет назад

Just realised it's a bit ironic that these computer science courses are called "crash" course. ;)

@jakekimds 7 лет назад

Crash Course rocket science... coming soon!

@tanxyrogue847 7 лет назад

coincidence isn't irony but that doesn't stop the phrase from being ironic

@bakedutah8411 7 лет назад

I wonder who first used "crash" to describe a computer getting into a fankle. It's such a common usage I'd never thought about it until you just mentioned it.

@AckzaTV 7 лет назад

no its not ironic because Crash Course was not made just fpr computer science, this is all brand new subject, man after they have every subject on earth done there will be No need for school or teachers and thank god

@justluc8556 6 лет назад

😂

@Revisiontecnica 7 лет назад

WHEN WILL THERE BE "ANOTHER LEVEL OF ABSTRACTION" TSHIRTS?!!!!

@biggerdoofus 7 лет назад

A bit of extra info about the making of custom file formats: since the data just needs to be in an order that the program using it can process, and that program is usually made by humans to at least some extent (though rarely entirely nowadays), it's also not uncommon to design new formats on top of text formats so that they'll be "human-readable". This is especially useful if you want users to be able to adjust data themselves, such as in the case of configuration files and simpler level editors for video games. That method also helps the data be easier to transfer across different computer architectures, which is why it's used in html and xml (formats used for websites and similar applications).

@Roxor128 7 лет назад

The downside, of course, is that text-based formats are rather space-inefficient and writing routines to read them isn't the simplest of tasks. Mainly because when it's human-readable, humans will edit it, and the mistakes they make are many and varied, requiring a lot of work on your part to figure out where they've gone wrong and come up with a suitable error message. Much like writing a compiler, actually. Most of the work there is making sure the file it's been fed is valid Foogol code (I hope nobody has made an actual language with that name because it's a good placeholder name).

@bee5120 7 лет назад

The best thing about SSD's? No defragmentation required.

@BertGrink 7 лет назад

Not only is it not required, but it would actually be detrimental to the "health" of the SSD, since each storage cell can only be written to a limited (albeit reasonably large) number of times.

@Leela_X 7 лет назад

미셜비 that only half the truth. ssds will preread/precache the next blocks just in case they are needed, defragmentation can have a performance benefit even on ssds

@andythepandaninja3859 7 лет назад

teleturbo Trying to defrag a SSD would do more harm than good as explained by Gert Brink Nielsen.

@Leela_X 7 лет назад

AndyThePandaNinja it depends how you defrag and what filesystem you use .

@NizarElZarif 7 лет назад

usually, SSDs have their own firmware and controller that knows what is the health of each block and where the data is best located. the controller along with the firmware handles defragment and file placement. this is much better than relying on your operating system since the firmware maintain optimal health and speed and reduce data corruption is best left to the manufacturer since each type of SSD uses different NAND types, and different controllers and different configuration.

@enricmm85 4 года назад

"Defragmentation [...] once upon a time it was really fun to watch." Indeed. RIP old Windows defrag tool 😢

@dowhile5948 5 лет назад

you have worked hard to make these videos.These videos are the best about computer science.

@vaibhavdeshmukh7900 5 лет назад

How I am so late to know about this amazing channel!!! I guess nowadays youtube is getting so much filled by shitty channels that awesome channels are getting missed!

@borriskarlov8140 5 лет назад

this series is SO empowering

@TheAAMoy 7 лет назад

HALT and CATCH FIRE, I miss the good old days.

@justplainc 7 лет назад

Tell me you also watch the show!

@austina2002 5 лет назад

I am glad to have found this series. Very informative. I will recommend to others!

@Lucuskane 7 лет назад

what a satisfying video, I love my file system

@michaniki1684 4 года назад

i always somehow end up coming back to this computer science crash course XD

@HH-zi2oj 6 лет назад

I learned a lot from Carrie Anne than my professors xD Thank you Crash Course! :D

@darylbangerter7171 7 лет назад

Looking forward to Crash Course: Interpretive Dance :)

@MOHx32 7 лет назад

I can't.... Stop..... BINGE WATCHING!!! I feel the knowledge coursing through my grey matter, ALMOST TO LEVEL 9000! WHAAAH!!!!

@utkarshupadhyay74 5 лет назад

Exactly what I was looking for.Thanks for spreading knowledge.

@ishbanyadav 7 лет назад

Its really great that you are talking about things that relate more to everyone.

@abs_nobody 7 лет назад

well that's not the purpose of this series tho

@madLphnt 7 лет назад

hahaha, the title is computer science not physiology

@tahir1156 4 года назад

Nice programme

@BBBuilds12 7 лет назад

Ext4 is the best!

@archlinuxrussian 7 лет назад

Correctrix *xfs ;3 lol. I think we can all agree these three are better than HFS+ ;)

@eddiesantos7232 7 лет назад

But... don't you like case-insensitive filenames, strange extended attribute storage, and a *special* version of Unicode denormalization applied to every filename? :p

@rydohg 7 лет назад

archlinuxrussian Umm, actually FAT32 is the best file system

@hugosz283 7 лет назад

My 5GB files disagree :P

@markgriz 7 лет назад

You kids get off my lawn. FAT12 forever!

@AuburnKamstra Год назад

this episode makes me desperately want a crash course linux series (sincerely, a braindead Ubuntu user)

@hiteshchand 4 года назад

superb ...

@ErikDaGreat 6 лет назад

i remember my father doing defragmentation on windows xp. it was about 7-8 years ago. i remember it was so colourful

@miklos. 7 лет назад

Love the series so much!

@LinhNguyen-bp9hd 4 года назад

that clears up a lot, cant believe I have just understood fragmentation after 20years using computer

@seanlee566 Год назад

Love that the part about 'deleting a file' is the most replayed

@رحمةعثمان-خ3ج 7 лет назад

this is agood lesson and you are a good teacher

@arnavattri5047 6 лет назад

Way awesome then Galvin Book!

@avi12 6 лет назад

I'm fascinated by how you explain about metadata and data! So cool!

@sss2393 4 года назад

Big fan of your teaching. Awesome as always, thanks a ton!

@tuseroni6085 7 лет назад

fun little aside about ascii: take the number of the letter you want to encode (count your alphabet, 1 for a 2 for b etc) then add 64 for uppercase or 96 for lowercase, and that's the number in ascii or utf8. if you are looking to do it in binary, and know how to count in binary, add 10 to the beginning of the number for uppercase and 11 for lowercase (or bitwise or 1000000 or 1100000. so for a you just take 00001 and add 11 to the beginning to get 1100001 for a lowercase a..you can go through your alphabet like this, 00001,00001,00010,00011,00100,00101,00110,00111,etc) if you know how to count in binary on your hands you can just count as you go through your alphabets and get the result in binary on your hand.

@RaymondHng 7 лет назад

You cannot do that with EBCDIC encoding because of its not non-contiguous letter sequences.

@tuseroni6085 7 лет назад

why would you make an encoding scheme with non-contiguous letter sequences?

@RaymondHng 7 лет назад

tuseroni Extended Binary Coded Decimal Interchange Code (EBCDIC) is an eight-bit character encoding used mainly on IBM mainframe and IBM midrange computer operating systems. EBCDIC descended from the code used with punched cards and the corresponding six bit binary-coded decimal code used with most of IBM's computer peripherals of the late 1950s and early 1960s. It descended from Hollerith encoding used on punch cards. The letters A through I consisted of a punch in the 12th row and a punch in the first through ninth row. The letters J through R consisted of a punch in the 11th row and a punch in the first through ninth row. The letters S through Z consisted of a punch in row zero and a punch in the second through ninth row.

@tuseroni6085 7 лет назад

that doesn't answer the question of WHY?

@RaymondHng 7 лет назад

A punch card consisted of 80 columns with twelve possible punch rows. Hollerith encoding consisted of one hole punched for a number, two holes punched for an alphabetic character, and three holes for punctuation characters. Punching more holes in a column weakens the card causing it to jam in high-speed card readers. When IBM developed their Series/360 mainframes in the 1960s, ASCII encoding had not been created.

@endlessbattle9122 2 месяца назад

Thanks for the knowledge ❤

@kannanhassouna8789 4 года назад

i love this series so much

@learning-master8259 Год назад

Incredible and informative ...

@ulysses_grant 5 лет назад

Thank you, I finally figured out what is metadata, and why it has this f...antastic name.

@menkiguo7805 4 года назад

Wait, so SSD is not write in order?r

@ronsxx78 5 лет назад

Crashcourse is better than my college professors

@MakeMeThinkAgain 7 лет назад

I so wish you would go into the details of defragmentation. Whenever I defragmented a drive I was CONVINCED I could come up with a better method. My theory is that someone came up with a very slow approach that worked well enough in the 1950s and then everyone kept using it. Prove me wrong!

@BlommaBaumbart 5 лет назад

2:14 - I understood that reference.

@josephpark2093 5 лет назад

? What reference?

@TriaMaxwell 7 лет назад

Does the Mongol Warrior file have a bug where it benefits from an "exception"? Or is that a feature?

@chaosof99 7 лет назад

I would have loved to see a little bit mentioned about file compression here, or maybe this is in an upcoming episode.

@hciprof 7 лет назад

The force is strong with you. It's episode 21 :)

@Mike-vj8do Год назад

These guys are awesome

@PongPongKiddo 5 лет назад

good explanation

@jayvl09 7 лет назад

I think it might be worth mentioning a single file can have multiple paths. Also that hierarchical ordering mechanisms like folders aren't the only solution. We might see non-hierarchical tag-based filesystems in the future.

@cdg03 7 лет назад

Fantastic, logical, well structured explanation. Thank you so much.

@addison1977 4 года назад

This series is so good

@ler9251 4 года назад

Number of abstraction level > storage space in my head👍

@beccaknowlton4858 7 лет назад

It would be really nice if there was a Business CrashCourse

@creationpower333 Год назад

Amazing content!

@NalinX 7 лет назад

really wonderful presentation. I love this series. Also, Carrie Anne 😍

@bansika63 4 года назад

fast speaking and confidence in subject .

@quitoxictv8307 Год назад

the fact this is free blows my mind

@Joetechlincolns 7 лет назад

I remember loading programs through DOS on start up. Changing command prompts etc. Now, all I ever deal with is testman errors using FORD scan tool software. No clue with all this new stuff.

@bayroncabrera7566 2 года назад

This is so amazing, i cannot thank you enough for such a wornderful job.

@ebuzertahakanat 5 лет назад

this great explanation but i knew it all of them and i watched to learn about togglable file systems which is not part of video and i still have 0 clue about what it might be.

@mohamedabdelaal8582 5 лет назад

this is sooo well put together! thank you!!!!

@happyfakeboulder644 6 лет назад

1:11 says "Hi, I'm Carrie Anne" in UTF8/ASCII 8-bit

@happyfakeboulder644 6 лет назад

well i'm an idot i didn't realize they would show the results 15 seconds later 2 minutes of my life wasted

@StephenGillie 7 лет назад

A show about computer files, by computer philes, for computer philes.

@guyr989 6 лет назад

This explains so much!! wish I could liked it more times

@rjwhite4424 7 лет назад

please continue to make these videos. They are awesome to computer nerds like me.

@davidepaula 7 лет назад

I absolutely love this series. Thank you for putting this together. Do you mind sharing that Putin.jpg [9:45] file that was inside the WORLD_HISTORY directory? Oh, and tell Stans that saving passwords inside a .txt file is not a very good idea. ;-) . I know you have already done 20 of these in Computer Science, but please keep them coming. Thank you.

@UnpopularName 6 лет назад

you were thinking Putin.jpg? i was wondering what Skoodilypoop_Animation.mp4 was...

@mohammadabdullahansari6314 6 лет назад

You can find that in World History.

@bautistavazquez6295 7 лет назад

This is pretty cool keep it up I wanna be a hardware engineer but I like learning about everything

@DavidsKanal 6 лет назад

This was so informative, loved it. Thanks so much!

@bipulkalita5780 6 лет назад

very good explanation.

@AldoOjeda 7 лет назад

Where are my "new level of abstraction" shirts and tote bags?

@tanveerB5 5 лет назад

wow, What an explanation. Thoroughly enjoyed the video. Like The concept taking from the very basic. Thanks :):)

@Roxor128 7 лет назад

I'm surprised the music directory didn't include a file named "NVRGVUUP.WAV".

@ElderBard00 4 года назад

Liked and subscribed! Loved this video. Thank you!!!

@chrisshyi8999 7 лет назад

Very educational, keep the great content coming!

@todkapuz 7 лет назад

yeah I miss watching defrag operations that were visually represented.

@carolynbrown1664 7 лет назад

I want too"" learn all I can about science & technology good to learn what we don't know thanks

@Morphineck 5 лет назад

First I though, man I'm weird, shouldn't red+green+blue = black. Then I was vindicated as you said that it was fun to watch the defragmentation process, I honestly thought I was the only one.

@csvscs 7 лет назад

really enjoying this series

@agimcomas 5 лет назад

Very helpful. Thank you.

@ajaxhopper9859 7 лет назад

Hey, y'all gonna go more in depth about graphics?

@poppop-oj6by 7 лет назад

Oreo Cakester Graphics is a complicated subject. Even if they cover it wouldn't go deep enough to be of reall value I think. Maybe they'll explain some basic concepts.