Russian (русский язык, transliteration: russkiy yazyk) is the most geographically widespread language of Eurasia, the most widely spoken of the Slavic languages, and the largest native language in Europe.
(sourced from http://en.wikipedia.org/wiki/Russian_language)
Russian belongs to the family of Indo-European languages and is one of three living members of the East Slavic languages, the others being Belarusian and Ukrainian (and possibly Rusyn, normally considered a dialect of Ukrainian).
Written examples of Old East Slavonic are attested from the 10th century onwards. Today, Russian is widely used outside Russia. Over a quarter of the world's scientific literature is published in Russian. Russian is also a necessary accessory of world communications systems (broadcasts, air- and space communication, etc). Because of the status of the former Soviet Union as a superpower, Russian had great political importance in the 20th century. Hence, the language is one of the six official languages of the United Nations.
The Russian language is primarily spoken in Russia, Ukraine, Kazakhstan and Belarus, and, to a lesser extent, the other countries that were once constituent republics of the USSR - for those in Europe see Category:European former CIS.
For a list of countries where Russian is the or an official language see Category:Russian-speaking countries