Official Russian currency is Russian Ruble. 1 Russian Ruble equals to 100 Russian kopeiks (cents).

At present there are 10-, 50-, 100-, 500, 1000 and 5000-Ruble banknotes, 1-, 5-, 10-, 50-kopeik coins and 1-, 2-, 5-, 10-Ruble coins in the circulation in Russia.
Foreign currencies are not legally accepted in the shops, hotels, bars, restaurants, etc. Foreign currency can be exchanged at most banks.

Credit cards in Russia.
Big shops and many hotels and restaurants in big cities accept credit cards. ATM-machines can be found easily. However, in smaller towns and villages it is sometimes impossible to use credit cards due to the fact that ATM-machines are not available and the cards are not likely accepted in the shops.

Traveller's cheques in Russia. Traveller's cheques are not widely spread, though some banks accept them.