In August 2006, shortly after Amazon launched its new cloud storage service Amazon S3, the company followed with a new cloud computing service called Amazon EC2, or Elastic Compute Cloud. Amazon EC2 provides resizable compute capacity in the cloud, allowing developers to launch various sizes of virtual servers within Amazon data centers.
Like its predecessor Amazon S3, Amazon EC2 initially operated solely as a RESTful API. Amazon did not introduce a web interface until three years later.Using the Amazon EC2 API, developers can launch small, large, and extra-large servers, paying only for the hours their servers are running. Amazon EC2, combined with Amazon S3, has laid the foundation for the next generation of computing, with APIs at its core.