What is an "Ad Lib"?

When you say something off-the-top of your head you are "ad libbing." Some highly skilled, and incredibly funny, improvisation performers have made careers from ad libs. Ironically, it takes a great deal of practice to develop improvisation skills.

The abbreviated term "ad lib" comes from the latin phrase: ad libitum which means "At one's pleasure."But sometimes resorting to an ad lib is anything but pleasurable.
For an actor who forgets a line during the middle of a show, an ad lib might be the only way to keep the scene going. Have you ever "ad libbed" your way out of a sadly sloppy scene? Did anyone notice? Was your ad lib better than the original script?

Leave a comment and share with us your on stage "ad lib" moments.