Avro is a remote procedure call and serialization framework developed within Apache's Hadoop project. It uses JSON for defining data types and protocols, and serializes data in a compact binary format. wikipedia.org

The eBay API is the heart of the an Application programming interface for interacting directly with the eBay database. The communication occurs over the Internet in the XML format. wikipedia.org

A relational database is a database that has a collection of tables of data items, all of which is formally described and organized according to the relational model. wikipedia.org

Data scraping is a technique in which a computer program extracts data from human-readable output coming from another program. wikipedia.org

Python is a general-purpose, high-level programming language whose design philosophy emphasizes code readability. Python claims to combine "remarkable power with very clear syntax", and its standard library is large and comprehensive. 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

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

Django is a high-level Python Web framework that encourages rapid development and clean, pragmatic design. wikipedia.org

Flask is a lightweight web application framework written in Python and based on the Werkzeug WSGI toolkit and Jinja2 template engine. It is BSD licensed. wikipedia.org

nginx (pronounced engine-x) is a Web server and a reverse proxy server for HTTP, SMTP, POP3 and IMAP protocols, with a strong focus on high concurrency, performance and low memory usage. 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

HTML5 is a language for structuring and presenting content for the World Wide Web, and is a core technology of the Internet originally proposed by Opera Software. It is the fifth revision of the HTML standard. wikipedia.org

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

Database design is the process of producing a detailed data model of a database. wikipedia.org