Crontab edition

crontab.sh

# To use cron for tasks meant to run only for your user profile, add entries to 
# your own user's crontab file. Start the crontab editor from a terminal window:
$crontab -e

# Commands that normally run with administrative privileges (i.e. they are 
# generally run using sudo) should be added to the root user's crontab (instead of the user's crontab):
$sudo crontab -e

# see:
# https://help.ubuntu.com/community/CronHowto