Ruby is a dynamic, reflective, general-purpose object-oriented programming language that combines syntax inspired by Perl with Smalltalk-like features. It was also influenced by Eiffel and Lisp. Ruby was first designed and developed in the mid-1990s by Yukihiro "Matz" Matsumoto in Japan. wikipedia.org

Java is a programming language and a core component of Oracle Corporation's Java Platform. The language derives much of its syntax from C and C++ but has a simpler object model and fewer low-level facilities. wikipedia.org

jQuery is a cross-browser JavaScript library designed to simplify the client-side scripting of HTML. Its syntax is designed to make it easier to navigate a document, select DOM elements, create animations, handle events, and develop Ajax applications. wikipedia.org

Ruby on Rails, often shortened to Rails or RoR, is an open source full-stack web application framework for the Ruby programming language. wikipedia.org

Web development is a broad term for the work involved in developing a web site for the Internet (World Wide Web) or an intranet (a private network).

The Twitter API allows other web services and applications to integrate with Twitter. It currently supports website embedding, a REST API, a streaming API, a framework for the iOS, and the OAuth authentication protocol.

Heroku is a cloud platform as a service (PaaS) run by the San Francisco, California-based company with the same name. Heroku led the way for a multi-language PaaS, introducing the 'polyglot platform'. Heroku PaaS now supports six languages: Ruby, Java, Node.js, Scala, Clojure and Python cloud PaaS. wikipedia.org

The Facebook Platform provides a set of APIs and tools which enable third-party developers to integrate with the "open graph" whether through applications on Facebook.com or external websites and devices. wikipedia.org

Bootstrap is a front-end toolkit for rapidly developing web applications from the developers of Twitter. It is a collection of CSS and HTML conventions that provides typography, forms, buttons, tables, grids, and navigation for a website.