Reddit is an online platform that enables users to submit links, create content, and have discussions about the topics of their interest. Users can post links to content on the web and then the other users can vote the posted links up or down, causing them to appear more or less prominently on the sites home page. The site has discussion areas where users can discuss the posted links, and vote for or against others comments. When there are enough votes against a given comment, it will not be displayed by default, although a reader can display it through a link or preference. Users who submit articles that other users like and subsequently "vote up" receive "karma", points which a user receives as a reward for submitting interesting articles. The posts on the site are classified under topics such as random, gadgets, sports, gaming, pics, videos, music, funny, movies, books, history, food, philosophy, television, jokes, art, and more. Reddit also includes several topical sections called subreddits, which focus on specific topics, including programming, science, and politics. Reddit was launched in 2005 by Alexis Ohanian and Steve Huffman and is based in San Francisco, California.