DESCRIPTION: Rsync is a tool to synchronize directories and files using a fancy delta copy algorithm. rsync is a utility that keeps copies of a file on two computer systems. It is commonly found on Unix-like systems and functions as both a file synchronization and file transfer program. The rsync algorithm is a type of delta encoding, and is used to minimize network usage. Zlib may be used for additional compression, and SSH or stunnel can be used for data security.