A file archiver is a
computer program that combines a number of
files together into one archive file, or a series of archive files, for easier transportation or storage. Many file archivers use
lossless data compression in order to reduce the archive's size.The most basic archivers just take a list of files and concatenate their contents sequentially into the archive. In addition the archive must also contain some information about at least the names and lengths of the originals, so that proper reconstruction is possible. Most archivers also store
meta-data about a file that the
operating system provides, such as timestamps, ownership and access control.
See more at Wikipedia.org...