Compression: Crash Course Computer Science #21


Get your first two months of CuriosityStream free by going to and using the promo code “crashcourse”. So last episode we talked about some basic file formats, but what we didn’t talk about is compression. Often files are way too large to be easily stored on hard drives or transferred over the Internet – the solution, unsurprisingly, is to make them smaller. Today, we’re going to talk about lossless compression, which will give you the exact same thing when reassembled, as well as lossy compression, which uses the limitations of human perception to remove less important data. From listening to music and sharing photos, to talking on the phone and even streaming this video right now the ways we use the Internet and our computing devices just wouldn’t be possible without the help of compression.

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  1. Ch Hussain says

    How we can justify compression?

  2. {VG} GAMER says


  3. Akram BenMhidi says

    Are all those compressions methods available in our Famous WinRAR ?Or are we supposed to use another one that is more specialised ?? Can you suggest… ?

  4. v.shiva raman says


  5. amal sal says

    You go girl, excellent.

  6. Arshar Android says


  7. oded solomon says

    9:25Help! Help!I'm being compressed!!

  8. mark rampage ramos says

    Jin Yang!!!

  9. Quack Head says

    2:39 hahahahahaahhaha look at bottom right corber hahaha big funmy

  10. geometry dash says

    that fringe tho and ur head shape mmmm

  11. geometry dash says

    nice teeth donkey.

  12. Cargill Seiveright says

    This series is a lot better than my University lectures

  13. sack boy 166 says

    C O M M P R E S S

  14. Johnson AY says

    So cool! Thanks for this series!

  15. Mikoo says

    Middle Out

  16. D.E. Sarcarean says

    It should be noted that the concept of compression was pioneered by Huffman in the 50s and it predates computer science.

  17. Lemon Cola says

    8:13 do i look like i know what a jpg is, i just want a picture of a got dang hotdog

  18. Планета Земя says

    Thanks for the video !

  19. Oliver Mainey says

    Found it weird that you grouped blocks of two different colors before you just make a pallete. There's 3 colors so thats 9 bytes + 16 * 2 bits = 13 bytes. I guess it was to show off the binary tree thing but the example seemed a bit off.

  20. OrokuSaki1986 says

    How long until internet speeds are good enough to the point where we only rarely use compression?

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