The pause function stops momentarily the
execution of a program.
Pressing <Enter> continues the execution; typing 'stop'
(without quotation marks) ends the program.
Usage
pause(duration = Inf)
Arguments
duration
numeric or infinite.
If duration is infinite (the default), then a pause is
made until the user presses <Enter> or types 'stop'.
Else if x = duration is a number, then a pause is made
during x seconds.