The document introduces Railsgoat, a purposefully vulnerable Rails application created by Ken Johnson for security training. It aligns with the OWASP Top 10 2010 vulnerabilities and is meant to be hacked and tweaked. Instructions are provided on how to get started, install it, and contribute code to the open source project hosted on GitHub. Future plans include updating it to work with Rails 4 and align with the OWASP Top 2013 vulnerabilities.