Short answers, pulled from the story.
Instagram officially released on the 12th of October 2010 after launching as Burbn Beta six days earlier. The team renamed the application from Burbn to Instagram and immediately saw a surge in popularity reaching one million registered users within two months.
Kevin Systrom and Mike Krieger created the prototype known as Burbn which appeared on the App Store on the 6th of October 2010. They had previously released a basic web-based version of Burbn online on the 21st of October 2009 before developing the mobile app.
Facebook acquired Instagram for approximately US$1 billion in cash and stock with the deal closing on the 6th of September 2012. The final purchase price consisted of $300 million in cash plus 23 million shares of Facebook stock approved by Britain's Office of Fair Trading on the 14th of August 2012.
Internal Meta research published by The Wall Street Journal in 2021 found that Instagram has negative effects on the body image of one in three teenagers. Seventy percent of teen girls and forty percent of teen boys experience negative social comparison regarding appearance while thirteen percent of British and six percent of American teenager users with suicidal thoughts could trace them to Instagram use.
The Android version of Instagram launched on the 3rd of April 2012 and was downloaded more than one million times within less than one day. At the time of this announcement 80% of Instagram's 600 million users were located outside the United States.