Hi! Welcome to Wikipedia, and thanks for noticing (and fixing) the vandalism on Chair. If you look at the top of any article, you'll see a tab that says "history." That's a list of every edit that's been made to any article. Check out the history tab on Chair, you'll see your edits there. Those 2 IP addresses under your name were the edits that messed up the article. If you click the link that says "prev," you'll see a comparison of that edit to the way the article looked before. That way, you can see just what was changed during each edit. If there's only been one bad edit, you can look at the comparison and click the link that says "undo" and the last edit will be removed.
You seem to be new around here. If you like, I'll be happy to gather up a few links for you that explain the basics of editing. Just let me know. I'll be watching this page, or you can leave a message on my talk page by clicking the link that says "Talk" in my signature. Joyous! | Talk 00:34, 2 February 2009 (UTC)