Monday Senator Sanders will be on reddit answering questions as part of their Ask Me Anything series, as the tweet says: Monday 4pm ET.

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One of the most popular subreddits is IAmA (“I Am A”) where a user may post “AMAs” (for “Ask Me Anything”), or similarly “AMAAs” ( for “Ask Me Almost Anything”) – prompts for others to ask questions about any topic. AMAs are open to all Reddit users, and use the site’s comment system for both questions and answers.

A number of notable individuals have participated in the IAmA subreddit, including President Barack Obama[17][18] (while campaigning for the 2012 election), Madonna, Chris Hadfield (who answered questions from the International Space Station), Bill Gates, Ron Paul, Stephen Colbert, Psy, Arnold Schwarzenegger, Rachel Maddow, Renée Fleming, Morgan Freeman, Louis C.K., Roger Federer, Larry King, Philip Zimbardo, Stan Lee, John Mather, David Copperfield, Paul Krugman, Danny Boyle, Al Gore, Roger Ebert, Michael Bolton, Gary Johnson, Lawrence Krauss, Jill Stein, Kevin Rudd, Amanda Palmer, and Tim Ferriss. As of October 2013, Barack Obama’s AMA is the highest rated on the site; the increased traffic brought down many parts of the website when the AMA occurred on August 29, 2012.

Celebrities participating in IAmAs have seen both positive and negative responses. Woody Harrelson’s AMA was criticized after Harrelson declined to answer questions that were unrelated to the movie “Rampart” he was promoting. In contrast, rapper Snoop Lion attracted 1.6 million page views after conducting an AMA that provided several candid responses to the community’s questions.