A location is the position of the current point in a buffer at some time in the past. Locations are recorded automatically by the editor for most commands that take you to a different buffer or where you might lose your place within the current buffer (for example Beginning of Buffer). They are designed to be a more comprehensive form of the mark ring (see Pop and Goto Mark), but without the interaction with the selected region.
Arguments: None
Key sequence: Ctrl+X C
Takes you back to the most recently recorded location. If a prefix argument count is supplied, it takes you back count locations in the location history. If count is negative, it takes you forward again count locations in the history, provided that no more locations have been recorded since you last went back.
Arguments: None
Key sequence: Ctrl+X M
Takes you back to a previously recorded location, which you select from a list.
Any prefix argument is ignored.
Arguments: None
Key sequence: Ctrl+X P
Takes you back to the next location in the ring of recorded locations. If a prefix argument count is supplied, it takes you forward count locations in the location history. If count is negative, it takes you back count locations in the history.
LispWorks Editor User Guide (Unix version) - 9 Dec 2014