Cron

Entry - Description Equivalent To :

@reboot - Run once, at startup. None
@yearly - Run once a year 0 0 1 1 *
@annually - (same as @yearly) 0 0 1 1 *
@monthly - Run once a month 0 0 1 * *
@weekly - Run once a week 0 0 * * 0
@daily - Run once a day 0 0 * * *
@midnight - (same as @daily) 0 0 * * *
@hourly - Run once an hour 0 * * * *

*/120 07-22 * * * Once every 2 hours but only between 7 am and 10 pm