This is a beginner tutorial on using crontabs or cron jobs in your LAMP (Linux/Apache/MySQL and PHP) web hosting account. Crontabs can be used to automatically execute server side commands, such as a PHP script, at periodic intervals. You can specify these periodic intervals, whether you want the script to be executed hourly, daily, weekly, and so on.

Read the full article here: Cron Job Tutorial: Crontab Scheduling Syntax and Script Example

For more discussion go here: Blog Article Discussion