Here is what Wikipedia says about Instagram: Instagram is an online mobile photo-sharing, video-sharing, and social networking service that enables its users to take pictures and videos, and share them either publicly or privately on the app, as well as through a variety of other social networking platforms, such as Facebook, Twitter, Tumblr, and Flickr.
Wikipedia later goes on to say: Instagram was created by Kevin Systrom and Mike Krieger, and launched in October 2010 as a free mobile app. The service rapidly gained popularity, with over 100 million active users as of April 2012 and over 300 million as of December 2014. The service was acquired by Facebook in April 2012 for approximately US$1 billion in cash and stock.
Many celebrities have profiles on Instagram, sharing photos and videos of their personal and professional lives with fans. Some celebrities deleted their accounts in response to Instagram’s proposed change to its Terms of Service, which would have allowed the photo-sharing app to sell images to advertisers without compensation to users.