The "s-10" came off in '94 and the little small blazer became known as the "s-blazer". I don't remember what the "s" standed for, I forget now. As for the S-10 being different that the S-10 blazer, the powertrain was identical all through the years. The main difference was in 94, when the newer model 2nd gen for the S-10 were introduced, and the 1st gen older style blazer was in production until the '95model year, 2nd gen blazer/jimmy's were introduced. The Powertrain was alomst always identical all through the years.
To clairfy;
When I say identical powertrain wise, I do have to clarify. As Blazee mentioned the engine choices, with the exception of the early 80's the blazer/jimmy never got a 4 cylinder engine. Other than that, the V'6's were almost always avaliable the same time, along with the trannies and rear ends.