What is Crontab?
Crontab (CRON TABle)is a program that manipulates the CRON daemon, making it easy for users to schedule task and run programs/commands at pre determined periods of time.
Crontab can also be considered a file witch contains commands that will be run by the system as the user that owns the
What is the purpose of Crontab?
Cron is designed to maintain a list of commands that the system needs to run at a given time interval.
For example if you have a script that generates statistics and needs to be run every couple of hours or everyday cron can do it for you. Or for example if you have a script that sends a newsletter every month you can use cron to run the script that sends the newsletter every month or week.