File Compression

Have you ever sent or downloaded a zip file?  Then you are already using without even knowing it.  Just about every time you download a file from the internet, it is zipped.  Before you are able to extract the files from the folder to make them usable, you have to unzip the folder.  What is the purpose of ?  The main purpose is for files to be transferred  faster and take up less space.  What zipping essentially does is reduce the amount of bits and bytes in the containing folder.

Most computer files have the same information listed over and over and over again. Computer files are fairly redundant in that sense, and what does is simply get rid of all the redundancy in a file. Rather than list the same exact piece of information over and over again, the program lists that information one time only, and then just refers back to it whenever it appears again in the original file. In this way, you can make your original file smaller, send it to someone else, and then have it end up an exact replica of the original file on the other end.

software works off of something like a library. The library contains something like a dictionary. Each piece of information in the file is assigned a specific value, perhaps something like a number, and then rather than repeating the piece of information every time it appears, the program replaces it with the corresponding entry in the library. That way, it simply writes down that short number instead of the whole piece of information, which could be very long.

You could actually recreate the compressed file on your own if you knew what library was used to compress it, much like using a decoder ring when you were a kid to spell out your top secret message. That is what a program does on the other end as it extracts a file and expands it back to its original form

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