h h h
Get a verbose or concise help screen, respectively.
 It would be more accurate to say, a concise help screen and an extremely concise help screen, respectively.
Get a line of help for the given debugger command.
View the specified manual page. If your system doesn't have a man command, it uses perldoc; the command may be overridden by setting the variable $DB::doccmd.
A.2.2. Stopping or Restarting
The q command exits the debugger (so does end-of-file on the terminal). The R command attempts to rerun the program with the state changes you made preserved. Some state may be lost; breakpoints, history, actions, option settings, and the -w, -I and -e command-line options will be preserved. ...