Wikipedia
Yandex.Translate (previously Yandex.Translation) is a web service provided by Yandex, intended for the translation of text or web pages into another language.
The service uses a self-learning statistical machine translation, developed by Yandex. The system constructs the dictionary of correspondences based on the analysis of millions of translated texts. In order to translate the text, the computer first compares it to a database of words. The computer then compares the text to the base language models, trying to determine the meaning of an expression in the context of the text.
It should be noted that the translation function obtained in the search results pages (on the button "Translate") appeared in 2009 and was carried out on the basis of PROMT.
Built in the Russian Wikipedia (translation from English into Russian).
In addition, the translator is built into the Yandex.Browser and automatically offers to translate text from supported foreign languages.