Shows the full path of (shell) commands.
Which is a utility that prints out the full path of the executables that bash(1) would execute when the passed program names would have been entered on the shell prompt. It does this by using the exact same algorithm as bash. Tildes and a dot in the PATH are now expanded to the full path by default. Options allow to rather print "~/" or "./" and/or to print all exectuables that match any directory in PATH.
