First of all I would like to introduce you with Instagram, it's an photo sharing app launched in October 2010 which allow users to take a photo, also apply a digital filter to it and then share it on various social networking sites, Including instagram's own.
On April 9 Facebook announced that they bought Instagram for $1 billion, its the first time Facebook is buying a company with huge number of users. Facebook offers photo and album sharing feature for its users but to provide the best photo sharing experience for their users Facebook spent $1 Billion.
A question may rise in your mind that, Why facebook bought Instagram ?
The answer is found in Zuckerberg’s own blog post :
This is an important milestone for Facebook because it’s the first time we’ve ever acquired a product and company with so many users. We don’t plan on doing many more of these, if any at all. But providing the best photo sharing experience is one reason why so many people love Facebook and we knew it would be worth bringing these two companies together.
But according to me the the exact meaning of this answer may be as follow :
Instagram is the exact opposite of Facebook. Facebook was scared and knew that one day instagram for the first time in its life the got a bigger and new competitor called as Instagram. As facebook doesn't offers such amazing photo sharing feature with digital filters so their users were use instagram to share albums and photos and this was a huge loss for facebook. Instagram was a big attack on Facebook's photo sharing. In less time Instagram acquired a huge success with over 30 Million registered users and this was a thing of challenge for Facebook.
To over come from this Facebook had bought Instagram. But another reason may be that want their users to have better photo sharing experience.