What does AMA and IAMA mean on forums like reddit?

On the social news website Reddit IAmA stands for "I am a" and AMA stands for "ask me anything".

In an IAmA post, a person will post what they are, and other people will ask the original poster about himself/herself.

Reddit was founded by two 22 year old University of Virginia graduates Steve Huffman and Alexis Ohanian in 2005, and claims to get more than 1,600,000,000 page views each and every month. It is one of the largest websites, with the greatest amount of traffic in the world.

You can find a list of upcoming AMAs here.

Of interest, Lars Rasmussen, Facebook’s Director of Engineering, recently did an AMA (ask me anything) on Reddit to discuss Graph Search. He answered 20 questions about the history, importance and technology behind the new experience. One of the most pressing questions was why Graph Search rolled out so slowly. Rasmussen says part of the delay can be blamed on privacy.