JavaScript: Updating DIV's with JQuery+AJAX and PHP+MySQL

Updating DIV's are easy to do with JQuery's AJAX library and some small PHP scripts. This is ideal for those who don't need huge PHP scripts, for people who need small scripts to interface with their users or keep counts on things. We are going to make a counter than can be updated by users. Any user that sees the page will be able to see the value increment and increment the value.