7-Zip is an open source file archiver, an application used primarily to compress files. 7-Zip uses its own 7z archive format, but can read and write several other archive formats. The program can be used from a command line interface, graphical user interface, or with a window-based shell integration. 7-Zip began in 1999 and is developed by Igor Pavlov. The cross-platform version of the command line utility, p7zip, is also available.7-Zip is open source software.