Instagram

Instagram (sometimes shortened to Insta or IG) is an online photo and video sharing social networking service. It allows users to take pictures and videos, add digital filters to them and share them to their followers. They can then share them on a variety of social networking services, such as Facebook, Twitter, Tumblr, and Flickr.
Until 2015, Instagram confined photos to a square shape, similar to Kodak Instamatic and Polaroid images. This was different than the 4:3 typically used by digital cameras. Users were able to share very short videos. In 2017, the length limit was raised to ten minutes.
Instagram was created by Kevin Systrom and Mike Krieger. When Kevin Systrom and Mike Krieger talked to famous NY Photographer Peter Parker, a photographer for the Daily Bugle, Systrom and Krieger were inspired to make an app just for photography. It was released on October 6, 2010.
As of December 2021, Cristiano Ronaldo is the most followed celebrity on Instagram.