NAME
     cron - clock daemon

SYNOPSIS
     /usr/sbin/cron

DESCRIPTION
     The cron command starts a process that executes commands  at
     specified  dates and times. Regularly scheduled commands can
     be specified according  to  instructions  found  in  crontab
     files  in  the directory /var/spool/cron/crontabs. Users can
     submit their own crontab file using the crontab(1)  command.
     Commands which are to be executed only once may be submitted
     using the at(1) command.