Ansible is a radically simple IT automation system. It handles configuration-management, application deployment, cloud provisioning, ad-hoc task-execution, and multinode orchestration - including trivializing things like zero downtime rolling updates with load balancers.
Many users run straight from the development branch (it's generally fine to do so), but you might also wish to consume a release.
You can find instructions [here](http://docs.ansible.com/intro_getting_started.html) for a variety of platforms. If you decide to go with the development branch, be sure to run "git submodule update --init --recursive" after doing a checkout.
If you want to download a tarball of a release, go to [releases.ansible.com](http://releases.ansible.com/ansible), though most users use yum (using the EPEL instructions linked above), apt (using the PPA instructions linked above), or "pip install ansible".
* Read [Community Information](http://docs.ansible.com/community.html) for all kinds of ways to contribute to and interact with the project, including mailing list information and how to submit bug reports and code to Ansible.
* All code submissions are done through pull requests. Take care to make sure no merge commits are in the submission, and use "git rebase" vs "git merge" for this reason. If submitting a large code change (other than modules), it's probably a good idea to join ansible-devel and talk about what you would like to do or add first and to avoid duplicate efforts. This not only helps everyone know what's going on, it also helps save time and effort if we decide some changes are needed.
* As of 1.8, modules are kept in different repos, you'll want to follow [core](https://github.com/ansible/ansible-modules-core) and [extras](https://github.com/ansible/ansible-modules-extras)
Ansible was created by [Michael DeHaan](https://github.com/mpdehaan) (michael.dehaan/gmail/com) and has contributions from over 900 users (and growing). Thanks everyone!