Amazon Simple Storage Service (Amazon S3) is storage for the Internet. It is designed to make web-scale computing easier.
You can use Amazon S3 to store and retrieve any amount of data, at any time, from anywhere on the web. It gives any developer access to the same highly scalable, reliable, fast, and inexpensive data storage infrastructure that Amazon uses to run its own global network of web sites. The service aims to maximize benefits of scale and to pass those benefits on to developers.