Using php for automatic emailing

[eluser]ramonekalsaw[/eluser]
I have a php file containing a list of 365 quotes and a script for displaying them on my ExpressionEngine-based website. (This script was created by another developer.)

Now I need to be able to modify this script so it can automatically email a 'quote of the day' to my mailing list.

I'm trying to figure out the php code I need to be able to do this type of automatic mailing.

Can anyone offer any tips for getting this done?

Thanks.