Founded by Kevin Systrom and Mike Krieger in October 2010, Instagram is an online mobile photo-sharing, video-sharing, and social networking service that enables users to share pictures and videos on a variety of social networking services, including Facebook, Twitter, Tumblr, and Flickr. Instagram also offers a variety of digital filters for users to apply to their images.
In January 2011, Instagram added the hashtag feature to help users discover photographs as well as other users. The app has spawned online trends like #ThrowbackThursday, and encouraged the proliferation of the “selfie,” self-portrait photograph typically taken with a cell phone or digital camera that has become very popular on Instagram.
Facebook acquired Instagram in April 2012 for $1 billion. By April 2012, Instagram announced there were more than 30 million Instagram accounts worldwide.