You wish to compose professional-grade programs: Rails is a full-stack, open source internet platform, with integrated support for unit, functional, and integration testing. It enforces good design principles, consistency of code along with the group (and throughout your business), and suitable release administration.
However, Rails is over just a pair of best practices. Rails make it both fun and easy to turn out quite a cool internet software. Want Ajax support, which means that your internet software is highly interactive? Desire a program that sends and receives email? Constructed in. Supports localization and internationalization? Constructed in. Would you want software with a REST-based port (so that they could socialize with other RESTful programs with hardly any effort on your own part)? All built in.