These directions explain installing chef-client or chef-solo on hosts that you would like to manage using Chef.
Chef Solo is a standalone version of Chef that runs locally on your node, detached from a Chef server.
Omnibus is a quick way to install Chef with an embedded version of Ruby, Rubygems, and other dependencies Chef needs. More information on it can be found on these pages:
Per Operating System Directions
The following are Operating System-specifc guides to installing Chef Client (or chef-solo) on a host. If your operating system is not listed, use the Other Operating Systems guide, which provides general instructions for install Chef using Rubygems as well as specific notes for various operating systems.
The following are the packages and gems required to install and run chef-client. The directions above handle the installation of all require dependencies. They are listed here for those wishing to install Chef via alternate means.
Gems written and provided by Opscode: