Almost every big company allows its data to be accessed by apps made by others. Facebook allows you to use your timeline on your own website. So does Twitter. On the other side, both services allow data from other sites to be shared on their timelines. You can make mobile apps that access the details of a user if his/her Facebook account is linked with your app. In fact, so many apps do not use their own login system, but rather use a service like Facebook, Google+ or Twitter to manage sign-up and login. How is it possible for you and so many other services to integrate so seamlessly with these world-renowned services? It is because these services provide a way to connect to their system and fetch and modify their data after sufficient authentication. This way of connecting to a service from another service is possible through a system called an Application Programming Interface (API). APIs have evolved rapidly and today it is possible to make connected, flexible and easy-to-integrate services using REST APIs. In this post, we will understand what an API is. Continue reading “Understanding API”