As a system administrator, it is very likely that you spend a lot of time doing recurring tasks on your system. Luckily for you, there is a way to automate tasks on Linux systems : cron jobs. Initially built in 1975 by the AT&T Bell Laboratories, cron has evolved to become a reference on Linux when it comes to scheduling and executing tasks at fixed dates or periods.

Source: LXer – Cron Jobs and Crontab on Linux Explained