This book is for web developers who are getting started with Rails and are looking for authentication solutions, as well as for Rails developers who are looking to extend their implementation of authentication with capabilities such as authorization and remote authentication. A fundamental understanding of Rails is required; readers should already be familiar with a few important Rails components such as bundler, migrations, models, views, and controllers. Basic knowledge of relational databases such as Ruby, HTML, and CSS is also required. should already be familiar with a few important Rails components such as bundler, migrations, models, views, and controllers. Basic knowledge of relational databases such as Ruby, HTML, and CSS is also required.