History of APIs - Amazon EC212 Mar 2011
In August 2006, shortly after Amazon launched its new cloud storage service Amazon S3, the company followed with a new cloud computing service dubbed Amazon EC2 or Elastic Compute Cloud.
Amazon EC2 provides resizable compute capacity in the cloud, by allowing developers to launch different sizes of virtual servers within Amazon data centers.
Just like its predecessor Amazon S3, Amazon EC2 was just a RESTful API. Amazon wouldn't launch a web interface for another three years.
Using the Amazon EC2 API developers can launch small, large and extra large servers and pay for every hour that the server is running.
Amazon EC2, combined with Amazon S3 has provided the platform for the next generation of computing with APIs at the core.