Hi. I have a system where I add emails and birthday dates.

Today, when it is someone´s birthday I log in the system and
manually send all greeting emails.

I was wondering If somehow my system at the server could
run by itself and identify that today is day X and that Y users are
celebrating their birthday so the system should AUTOMATICALLY sends
all the greeting emails WITHOUT me having to log in and pushing any button.

Is that possible?? How can I do that?
Thanks