To enter the territory of the Russian Federation foreign citizens must obtain a Russian visa, it is a paper document that is is stuck into your passport and permits you to stay in Russia for a certain period of time.
It reflects the date of entry and exit, travel information and passport details of its holder. In some cases, a photo of a holder is also attached.
A visa is issued by Russian consulates personally to a visa applicant, for more details see List of Consulates of the Russian Federation.
To obtain a Russian visa, you need a Visa invitation (If you are not holder of pasport of visa-free entry ). The invitation may be issued by a Russian organization with a special identification number accredited by the Ministry of Foreign Affairs. Full information on the documents required to obtain a Russian visa is provided by the consulate of the Russian Federation in your country (the list of required documents in different countries may vary).