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

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

JavaScript is a prototype-based scripting language that is dynamic, weakly typed and has first-class functions. It is a multi-paradigm language, supporting object-oriented, imperative, and functional programming styles. wikipedia.org

PostgreSQL, often simply Postgres, is an object-relational database management system (ORDBMS) available for many platforms including Linux, FreeBSD, Solaris, Microsoft Windows and Mac OS X. wikipedia.org

HyperText Markup Language (HTML) is the main markup language for web pages. HTML elements are the basic building-blocks of webpages. wikipedia.org

Cascading Style Sheets (CSS) is a style sheet language used to describe the presentation (that is, the look and formatting) of a document written in a markup language. wikipedia.org

MongoDB is an open source document-oriented NoSQL database system written in the C++ programming language. It manages collections of BSON documents. wikipedia.org

PostgreSQL, often simply "Postgres", is an object-relational database management system (ORDBMS) with an emphasis on extensibility and standards-compliance.

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).

Redis is an open-source, networked, in-memory, key-value data store with optional durability. It is written in ANSI C. The development of Redis is sponsored by VMware.