In the translation industry, CAT stands for “computer-assisted translation.” Although it may sound like it, “computer-assisted” does not mean “computer-translated” or “machine-translated.” Google Translate and other machine translation tools are not examples of computer-assisted translation. Popular CAT tools include Trados, Memsource, Wordfast, and OmegaT.
A CAT tool leverages previous translations done (hopefully) by a human translator. This is invaluable for ensuring consistency across chapters or files in a translation project. That makes CAT tools suited for use especially with manuals but also with websites, contracts, and more. The document to be translated is loaded into the CAT tool, in this case Trados, and converted into a CAT-friendly format as shown in the screenshot below.
There are two main elements: the translation memory and term bases. The translation memory (TM) records translations of whole sentences. When the same or a similar sentence comes up in the future, the CAT tool brings up that past translation and allows you to use it as-is or modify it if the match is not 100%. Term bases (TB) are glossaries containing individual words or phrases. The CAT tool scans the document for occurrences of these words or phrases and marks them to let you know that a preferred translation of the word or phrase exists.
In this screenshot, the area marked “1” is the TM window. It provides previous translations related to the current sentence (or “segment”) in the third area (source text). The TM may be provided by the client, or the translator may have put together their own. They can be built by genre or client.
The area marked “2” is the TB or glossary window. Like the TM, the TB may be prepared by the client or the translator.
The area marked “3” is the source text, and the area marked “4” is the corresponding translation.
Once the work is complete, the file is saved in the format of the original document, and the translation replaces the source text in the newly created file.