PHP Mysql

Ok I have a page where people can input text data into a database to be displayed as html later. But I want a fully functional php tool that will allow them to make bold and change font then submit it. So basically I need a php html editor so if they put a sentence in and whant it bold, the user can click a button to put the <b> </b> tags around the text. Or if they want to skip a like it will add the <br> or <p> tag. I know this is alot of work so i was wondering if there were any premade php applications any of you know of that will do this. Thanks,
trent

 

http://www.kevinroth.com/rte/demo.htm