Hi,
You meant Moscow Metro? Or Saint-Petersburg? They are different in many things, although the major principles, like having one platform with two rails by sides for opposite directions are same. This model was also used in other former Soviet republics. Also, it is, as they call it, a circular - radial one, means that it is composed of cirlces crossed with radial branches. Easy to understand.

In general, I can say that this system is easier to undestand and use than the systems I have seen for example, in New York (above ground) or in Madrid - many lines and rails at the same station, you need to choose the right train and not to miss the right station to exit.