Quote Originally Posted by Trzeci_Wymiar
In "Using Russian: A Guide to Contemporary Usage" Derek Offord and Natalia Gogolitsyna maintain that there are three broad categories of dialects within Russian --

1. The Northern Dialects (North of Novgorod)

2. The Southern Dialects (From the Belarus and Ukraine borders to Kolomna)

3. The Central Dialects (Moscow, Pskov, Vladimir)

They differ in matters of phonology, grammar, and vocabulary.
They are говоры. Говор is not the same as dialect.
As for the difference in grammar and vocabulary - it's minimal and casual, and you can talk to someone from another region for hours, or even days or weeks, and not notice any difference in grammar and vocabulary in comparison with "standart" language. In fact, all the Russians speak "standart" language.

Anyway, using the word "dialect" as applied to the Russian language, is wrong, it only confuses foreigners because they think that there really are "dialects" with different grammar and vocabulary in Russian. But there are NOT.