Tumblr is a microblogging and social networking website founded by David Karp in 2007, and owned by Yahoo! since 2013. The service allows users to post multimedia and other content to a short-form blog. Users can follow other users' blogs. Bloggers can also make their blogs private. For bloggers, many of the websites features are accessed from a "dashboard" interface. As of December 1, 2016, Tumblr hosts over 324.7 million blogs. As of January 2016, the website had 555 million monthly visitors. Development of Tumblr began in 2006 during a two-week gap between contracts at David Karps software consulting company, Davidville (housed at Karps former internship with producer/incubator Fred Seiberts Frederator Studios which was located a block from Tumblrs current headquarters). Karp had been interested in tumblelogs (short-form blogs) for some time and was waiting for one of the established blogging platforms to introduce their own tumblelogging platform. As no one had done so after a year of waiting, Karp and developer Marco Arment began working on their own tumblelogging platform. Tumblr was launched in February 2007 and within two weeks, the service had gained 75,000 users. Arment left the company in September 2010 to focus on Instapaper.