There is a system utility called the cron that checks for jobs whenever you specify it to and performs your tasks that you give it. The way I use the cron is by setting up a side directory somewhere called cron or something like that. After that I make a file called cronjobs with an editor such as vi. The syntax looks like the following:
Minute, Hour, Day of Month, Month, Day of week (* means every possible time of that field)
a cron file could look like this (This would do a job every day at 1:30 PM)
30 13 * * * /home/myname/cron/myscript
then do # crontab cronjobs and the script myscript will be executed every day at 1:30 PM.
I hope I didnt confuse you more, there is plenty of documentation if I did
Hope this helps!