sources and the final dest are in the form of:
If the file is on the local host, a plain filename can be specified. If the file is on a remote host, the host must also be specified. user can optionally be specified to log in as a different user on the remote site (in which case a password prompt might appear) and port can optionally be specified with a remote host to make rsync use a TCP port other than its default, 873.
Relative filenames (names without initial slashes) are handled relative to the user's home directory. If a source directory is listed with a trailing slash, the whole directory is transferred and will appear under the destination directory; if the directory is listed without the slash, its files and subdirectories will appear directly under the destination directory. Normally, regular directories and files are transferred, but not symbolic links or other special files such as sockets and FIFOs.
Two other formats for sources and dest, which refer to files on an rsync server (rsyncd), are:
rsync servers are beyond the scope of this book