To learn more about configuring automated tasks, see the following installed documentation:
cron man page contains an overview of cron.
crontab man pages in sections 1 and 5:
anacron manual page contains an overview of anacron.
anacrontab manual page contains an overview of the
/usr/share/doc/at-<version>/timespec contains detailed information about the time values that can be used in cron job definitions.
at manual page contains descriptions of
batch and their command-line options.