https://www.debian.org/doc/manuals/system-administrator/ch-sysadmin-time.html Just as it hits 0 minutes in the day, cron job runs the task. For example, 00:00, 01:00, 02:00 and so on. If it hits 0 minute 24 times, that takes care of every hour in the day. (If not every hour then it would have been *) The 1 in 5th position represent Monday. You can use 1 or mon but not Monday.