How does file compression work?

Posted by Phoshi on Super User See other posts from Super User or by Phoshi
Published on 2010-04-18T14:26:59Z Indexed on 2010/04/18 14:34 UTC
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compression

So, I realised today I take file compression for granted. The ability to bundle a few files together into one, and have it come out smaller than any of them, is something I just accept as a fact, but how does it actually work?

I have a limited knowledge of it that includes something to do with replacing all the duplicate entries with pointers, to shrink that way, but beyond that I'm fairly clueless!

As I'm always open to new knowledge, as I imagine most of us here are, I thought I'd ask. So, SuperUser, how does compression actually work?

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