The less common way of compressing files is using bzip2. Like with gzip, the syntax is

$ bzip2 fileA fileB...

Using bzip2 adds the extension .bz2. To uncompress a .bz2 file, you can use the bunzip2 command.

$ bzip2 fileA.bz2 fileB.bz2...

If you want to use this command to zip or unzip every .bz2 file in your directory, use a wildcard.

$ bzip2 *
$ bunzip2 *