bottom of the screen with M-x and you should type the name of the
command; in this case, "replace-string". Just type "repl s<TAB>" and
Emacs will complete the name. (<TAB> is the Tab key, usually found
-above the lCapsLock or Shift key near the left edge of the keyboard.)
+above the CapsLock or Shift key near the left edge of the keyboard.)
End the command name with <Return>.
The replace-string command requires two arguments--the string to be