Ruby-Handbook is a project mainly written in ..., it's free.
A self-directed guide for learning Ruby
NOTE: This project has just started and does not yet have any finished activities. Please check back in the future. If you're interested in helping develop this guide, please contact Marty through Github messages.
This is a self-directed guide to learning Ruby. It can be worked through on your own or with a study group. We do encourage local communities to organize an event or series of gatherings to give those new to Ruby or programming the support to work through the activities.
The handbook is a collection of activities that may or may not be of interest to you on your path to becoming a Ruby programmer. Throughout the guide we will indicate which activities are highly recommended and which ones are considered optional. Each activity will have a description of what's involved, why it's important and how to go about completing the requirements.