The command to create/edit, list, and remove cron jobs is crontab.
If you call it with the -u option, it specifies the name of the
user whose crontab is to be tweaked. If this option is not given,
crontab examines "your" crontab, i.e., the crontab of the person
executing the command. If you are looged in as root and run crontab
without -u, then root's crontab is listed/modified/removed. If you
are logged in as exampleuser and run crontab without -u, then
exampleuser's crontab is listed/modified/removed."