[jaysh]

Fun fact: "tar xf FILENAME" will auto-detect the compression when extracting FILENAME. You don't actually need to specify "z" for gzip, "j" for bzip, etc.

[antientropic]

That's GNU tar specific, though.

[craftkiller]

Works in modern bsdtar also, and as of a couple years ago they also added support for the "-a" flag to do the same thing when compressing.