Crontab Examples

At every minute 
* * * * *

At every 10 minutes
*/10 * * * *

At every 15 minutes
*/15 * * * *

At every hour
0 * * * *

At every 2 hour
0 */2 * * *

Daily (00:00)
0 0 * * *

Everyday 8:00am
0 8 * * *

Every Saturday
0 0 * * SAT