What is "heroku"

Heroku is a multi-language cloud application that works like a Paas. With Heroku, you don’t have to worry about servers at any time. You can write your apps using the most modern language development practices of your choice, using features such as databases SQL and NoSQL, Memcached, and many others. To deploy the application, simply use a Git SCV and the application is automatically updated.

Today Heroku supports Ruby, Node.js, PHP, Pyton, Scala, Java and Clojure