What is a TM?

A translation memory, or TM Abbreviation: Translation Memory, is a type of database that is used in software programs designed to aid human translators. Translation memories are typically used in conjunction with a dedicated computer assisted translation (CAT) tool, word processing program, terminology management systems, multilingual dictionary, or even raw machine translation output.

A translation memory consists of text segments in a source language and their translations in one or more target languages. These segments can be blocks, paragraphs, sentences, or phrases. Individual words are handled by terminology bases or glossaries and are generally not stored in TMs.

Some translation memories systems attempt only literal matching, that is to say that they can only retrieve segments of text that match entries in the database exactly, while others employ fuzzy matching algorithms to retrieve similar segments, which are presented to the translator with differences flagged.

Segments where no match is found will have to be translated by the localization professional manually. These new segments are stored in the database where they can be used for future translations.

Translation memories work best on texts which are highly repetitive, such as technical manuals. They are also helpful for making incremental changes to texts, corresponding, for example, to minor product changes. Traditionally, translation memories have not been considered appropriate for literary or creative texts, for the simple reason that there is so little repetition in the language used. However, others find them of value even for non-repetitive texts, because the database resources created have value for concordance searches to determine appropriate usage of terms.

If a translation memory system is used consistently on appropriate texts over a period of time, it can save localization professionals considerable work.

Main Benefits

Ensuring that the translated content is consistent, including common definitions, phrasings and terminology. This is important when different localization professionals are working on a single project .
Accelerating the overall translation process; since translation memories "remember" previously translated material, localization professionals have to translate it only once.
Reducing costs of long-term translation projects; for example the text of online helps, software warning messages or collections of web pages need to be translated only once, and can be used several times.
For large localization projects, savings (in time or money) thanks to the use of a TM package may already be apparent even for the first translation of a new project, but normally such savings are only apparent when translating subsequent versions of a the original translated project.