When computers first came online one of the primary reasons was to transfer information.  As people started sending files over the internet the idea of compression took off.  Most people look a *.zip as the first format they used.  For the more serious file transferring people there where a variety of tools that came from the start such as *.rar and *.arj.  All of these took either a single file or a group of files and placed them in file under their extension in one file that was a smaller size than the originals.

Currently there a couple of file compression formats that are more prevalent than others.  Two of them are still from the beginning are using File Extension RAR ^[1] and File Extension ZIP ^[2].  Others that have joined the party are *.iso and *.daa.  The following two are used primarily when imaging a DVD or CD to be reproduced.

When using a compression format people can use different types for optimal use.  For a single file to be transferred the most popular is *.zip.  Windows can open and make these files with no additional software making it the easiest for people to use.  It is all proficient in grouping these files.  When you would like to break up a larger set of files into multiple files for easier transfer *.rar is the preferred format for most.  WinRar is the most common program associated with *.rar.  Using this format you will be able break these files into a group of files or one larger file.  The power in this format is that you can set the file size for each of the files to be broken down with.  Once the files are reunited people can take WinRar or another program and put them back together and retrieve the original files.

There is also another type of compression which became very popular called video and audio compression. Such compression for example is used in File Extension MP4 ^[3]. This type of compression is slightly different from usual since it allows lossy compression which allows losing some details of information to enable better compression.

While there are plenty of different types of compression formats out there they all do primarily the same thing.  One other reason many people use these formats is the ability to password protect files.  Many times this is one of the only reasons a file is compressed with today’s increasing internet speeds.  Whenever you run across a format you have never used you can easily get a freeware converter to convert to your preferred method.  Since the beginning of file transfers people have used compression to make transferring files easier with newer Medias coming out daily this will never change.  Now we are just experiencing video and music being compressed.