T ranslation: the fact of transposing a text from one language (the 'source' language) to another (the 'target' language) . Translators, specialists in their field, always work into their mother tongue (the 'target').
P roofreading: a comparison of the original text and the translation with a view to correcting any translation errors (misunderstandings, omissions, spelling and grammar errors, etc). Proof-readers, specialists in their field, always work into their mother tongue. The proof-reader is never the translator.
V alidation: thorough proofreading for the purpose of determining the accuracy of the corrections made by the proof-reader. In general done by the original translator, but where there is disagreement between the translator and the proof-reader, it can be done by a third translator specialising in the field working into his/her mother tongue.
B ack translation: a translation provided by translators working into one of their source languages and not into their mother (target) language. The purpose of a "back translation" for an end customer is to make sure that:
