This document is about Jenkins, an open source automation server that enables developers to reliably build, test, and deploy their software. It discusses how Jenkins can be used to automate tasks like building Java projects, running tests with tools like JUnit, and deploying code to servers like Amazon EC2, Google App Engine, or Windows Azure. The document also mentions that Jenkins supports integration with version control systems and platforms like Hadoop and can be used to continuously build and test code changes from tools like Git.