tar The .tar filename was originally designed to be used as a TApe ARchiver to store entire file systems and files as single files on tape storage medium. It was designed by AT&T in 1979. Today, the format more commonly refers to an archive or collation of multiple files into a single file with the .tar filename extension. The format is an open source file archive format commonly associated with the UNIX tar command however other data compression tools are capable of effectively compressing and/or decompressing files saved with the .tar file format. Doing so typically adds the compression filename extension to the archive file for example .tar.bz2.
zip The .ZIP file extension format is a file archive and data compression format originally developed and released in 1989 by Phil Katz. With compatible zip format software, a file or a group of files can be packed (compressed) into a single .zip archive which can later be unpacked (decompressed). The zip file archive format facilitates the distribution of multiple files as single archives particularly over the internet and networked systems. Many operating systems have native support for the file format and can usually open zip archives without the need for third party software. Microsoft windows for instance has had native support for the ZIP format since Microsoft Windows 98, similarly Apple's Mac OS includes ZIP support through its default archive file handle Archive Utility.