Go2Linux shows you how to setup a Cron Job under Linux

Cron jobs are added tasks to the cron daemon, for it to run them periodically, at specific times.
You usually want your jobs or tasks executed every, Monday, or every day at 5 pm, etc. Cron is very powerful and flexible, so you can tweak it a lot. Let's see what cron is.

Cron is a time-based job scheduler in Unix-like computer operating systems. Cron enables users to schedule jobs (commands or shell scripts) to run periodically at certain times or dates. It is commonly used to automate system maintenance or administration, though its general-purpose nature means that it can be used for other purposes, such as connecting to the Internet and downloading email

  Cron Job Linux: How to, guide, syntax and examples