Synopsis:

frame [frame-number]

Change the current frame to frame frame-number if specified, or the most-recent frame, 0, if no frame number specified.

A negative number indicates the position from the other or least-recently-entered end. So frame -1 moves to the oldest frame.

Examples:

   frame     # Set current frame at the current stopping point
   frame 0   # Same as above
   frame .   # Same as above. 'current thread' is explicit.
   frame . 0 # Same as above.
   frame 1   # Move to frame 1. Same as: frame 0; up
   frame -1  # The least-recent frame

See also:

up, down, and backtrace