Translation is the communication of the meaning of a source language text by means of an equivalent target language text. The English language draws a terminological distinction (which does not exist in every language) between translating (a written text) and interpreting (oral or signed communication between users of different languages); under this distinction, translation can begin only after the appearance of writing within a language community.
A translator always risks inadvertently introducing source language words, grammar, or syntax into the target language rendering. On the other hand, such “spill-overs” have sometimes imported useful source language calques and loanwords that have enriched target languages. Translators, including early translators of sacred texts, have helped shape the very languages into which they have translated.
Because of the laboriousness of the translation process, since the 1940s efforts have been made, with varying degrees of success, to automate translation or to mechanically aid the human translator. More recently, the rise of the Internet has fostered a world-wide market for translation services and has facilitated “language localization”.
A “back-translation” is a translation of a translated text back into the language of the original text, made without reference to the original text. Comparison of a back-translation with the original text is sometimes used as a check on the accuracy of the original translation, much as the accuracy of a mathematical operation is sometimes checked by reversing the operation. But the results of such reverse-translation operations, while useful as approximate checks, are not always precisely reliable. Back-translation must in general be less accurate than back-calculation because linguistic symbols (words) are often ambiguous, whereas mathematical symbols are intentionally unequivocal. In the context of machine translation, a back-translation is also called a “round-trip translation.” When translations are produced of material used in medical clinical trials, such as informed-consent forms, a back-translation is often required by the ethics committee or institutional review board.
Source and target languages
In the practice of translation, the source language is the language being translated from, while the target language, also called the receptor language, is the language being translated into. Difficulties in translating can arise from lexical and syntactical differences between the source language and the target language, which differences tend to be greater between two languages belonging to different language families.
Often the source language is the translator’s second language, while the target language is the translator’s first language. In some geographical settings, however, the source language is the translator’s first language because not enough people speak the source language as a second language. For instance, a 2005 survey found that 89% of professional Slovene translators translate into their second language, usually English. In cases where the source language is the translator’s first language, the translation process has been referred to by various terms, including “translating into a non-mother tongue”, “translating into a second language”, “inverse translation”, “reverse translation”, “service translation”, and “translation from A to B”.
Translation for specialized or professional fields requires a working knowledge, as well, of the pertinent terminology in the field. For example, translation of a legal text requires not only fluency in the respective languages but also familiarity with the terminology specific to the legal field in each language. While the form and style of the source language often cannot be reproduced in the target language, the meaning and content can.