On a side note, is there any actual difference other then the obvious one?
Yes.
They will only do what they're told when it's requested, for example; when a user is online.
If, however, a user is not online, making requests (clicking links) it will not run - although you can workaround that, with a little math.
Here's a few links:
time() - Return current time
glob() - Used to include all cron files, in my method
Some basic PHP knowledge
& of course, you need to know some math