Reddit (/ˈrɛdɪt/, stylized in its logo as Reddit) is an American social news aggregation, web content rating, and discussion website. Registered members submit content to the site such as links, text posts, and images, which are then voted up or down by other members. Posts are organized by subject into user-created boards called "subreddits", which cover a variety of topics including news, science, movies, video games, music, books, fitness, food, and image-sharing. Submissions with more up-votes appear towards the top of their subreddit and, if they receive enough votes, ultimately on the site's front page. Despite strict rules prohibiting harassment, Reddit's administrators spend considerable resources on moderating the site. As of February 2018, Reddit had 542 million monthly visitors (234 million unique users), ranking as the #3 most visited website in U.S. and #6 in the world, according to Alexa Internet, with 57.4% of its user base coming from the United States, followed by the United Kingdom at 7.5% and Canada at 6.3%. Across 2015, Reddit saw 82.54 billion page views, 73.15 million submissions, 725.85 million comments, and 6.89 billion upvotes from its users. Reddit was founded by University of Virginia roommates Steve Huffman and Alexis Ohanian in 2005. Condé Nast Publications acquired the site in October 2006. Reddit became a subsidiary of Condé Nast's parent company, Advance Publications, in September 2011. As of August 2012, Reddit operated as an independent entity, although Advance was its largest shareholder Reddit is based in San Francisco, California. In October 2014, Reddit raised $50 million in a funding round led by Sam Altman and including investors Marc Andreessen, Peter Thiel, Ron Conway, Snoop Dogg, and Jared Leto. Their investment valued the company at $500 million then. In July 2017, Reddit raised $200 million for a $1.8 billion valuation, with Advance Publications remaining the majority stakeholder.