CRON:
*    *    *    *    *  <command to be executed>
|     |     |     |    |
|     |     |     |    +—– Day of week (0 – 6) (Sunday=0)
|     |     |     +——- Month (1 – 12)
|     |     +——— Day of month (1 – 31)
|     +———– Hour (0 – 23)
+————- Min (0 – 59)
@reboot <command> #Runs at boot
@yearly <command> #Runs once a year [0 0 1 1 *]
@annually <command> #Runs once a year [0 0 1 1 *]
@monthly <command> #Runs once a month [0 0 1 * *]
@weekly <command> #Runs once a week [0 0 * * 0]
@daily <command> #Runs once a day [0 0 * * *]
@midnight <command> #Runs once a day [0 0 * * *]
@hourly <command> #Runs once an hour [0 * * * *]
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