Basic Concepts

Localization Localization is the process of adapting and manufacturing a product so that it has the look and feel of a nationally-manufactured piece of goods. It includes globalization, internationalization (preparation of products to facilitate localization), localization and translation (collectively called GILT). (The Localization Industry Primer – LISA)
Globalization Globalization is the transformation of business and processes to support customers around the world, in whatever language, country, or culture they require. (The Globalization Industry Primer – LISA)
Internationalization Internationalization is the process of enabling a product at a technical level for localization. In other words, an internationalized product does not require remedial engineering or redesign at the time of localization. (The Globalization Industry Primer – LISA)
Machine Translation Machine translation (MT) is a sub-field of computational linguistics that investigates the use of computer software to translate text or speech from one natural language to another.

Based on the approaches, there are rule-based MT, transfer-based MT, interlingual MT, dictionary-based MT, statistical MT, example-based MT, hybrid MT. (Wikipedia)

Translation Memory Translation memories, also known as translation databases, are collections of entries where a source text is associated with its corresponding translation in one or more target languages.Typically, TMs are used in translation tools: when the translator “opens” a segment, the application look up the database for equivalent source text. The result is a list of matches usually ranked with a score expressing the percentage of similarity between the source text in the document and in the TM. (opentag.com)