sudo vim crontab -e
1 2 3 4 5 /path/to/command arg1 arg2
1 2 3 4 5 /root/backup.sh
* * * * * command to be executed
- - - - -
| | | | |
| | | | ----- Day of week (0 - 7) (Sunday=0 or 7)
| | | ------- Month (1 - 12)
| | --------- Day of month (1 - 31)
| ----------- Hour (0 - 23)
------------- Minute (0 - 59)