You need to use crontab command for editing or setting up your own cron jobs.
There are two different types of configuration files:
1-The UNIX / Linux system crontab : Usually, used by system services and critical jobs that requires root like privileges. The sixth field (see below for field description) is the name of a user for the command to run as. This gives the system crontab the ability to run commands as any user.
2-The user crontabs: User can installer their own jobs using the crontab command. The sixth field is the command to run, and all commands run as the user who created the crontab.
1.To edit your crontab file, type the following command at the UNIX / Linux shell prompt:
$ crontab -e
2.Your cron job looks as follows for user jobs:
1 2 3 4 5 /path/to/command arg1 arg2
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