What is data compression?

data compression is a general term for a group of technologies that code large files to reduce them. Smaller files occupy less space and leave more storage space. They are also faster to transfer network, whether this network is the Internet, intranet or local network (LAN).

In the 70s. The idea was soon extended by the data compression techniques, so the term "archive" is now often used to describe a compressed file.

Data compression includes the use of an algorithm that makes some recurring bits unnecessary. It's a bit like a kind of shortcut map that is stored in a compressed file. After decompressing, the map restores all the missing bits and reconstructs the entire file. This technique can be used with text, graphics, executable programs and multimedia movies, although some file types compress better than itNo.

Today's most commonly recognized data compression technique was originally used in the DOS operating system before Microsoft Windows ™ has become ubiquitous in the mid -90s. The author Phil Katz eventually called these compressed files zip files - the idea is that when the files were unpacked (decompressed), the entire content "jumped". The files used with this method have an extension, .zip .

Files that are extremely large, even if they are compressed, can be divided into pieces before sending over the net. The pieces are collected and re -assembled at the receiving end. The leading compression technique for large files, also from DOS Days, is called rar , after the author of Eugene Roshal. Programs that support r Oshal ar chives can create a set of Rars from a large multimedia file or decompressan existing rar that re -assembles a movie or a program. These files have the extension .rar or for multi -part files, part01.ra, part02.ra or .R01 R02 .

various formats of music formats also use other techniques of data compression to detain files while maintaining as much original quality as possible. The most visible example is the .mp3 format. In this case, however, a compressed file is not an archive and cannot be decompressed. Bits that are removed to achieve a smaller file size are gone forever. Other techniques used for music files retain more quality, but also have a larger file size.

Data compression programs are widely available online. The zip or rar'd file requires a program that supports this method for unpacking or UNRAR. Most programs support multiple types of compressed files and many of these programs are freeware.