Syntax of crontab

This is the anatomy of a Crontab:

* * * * * <username> /path/to/command <args>

The * represents a time unit, as follows:

1 2 3 4 5

1 = Minute (0 ~ 59)
2 = Hour (0 ~ 23)
3 = Day of month (1 ~ 31)
4 = Month (1 ~ 23)
5 = Day of week (0 ~ 7 being Sunday 0 or 7)