It is indeed. The rulebook in the Essentials Kit is a really great summary of the game.

Actually, the Essentials Kit as a whole is pretty solid. I'm not a fan of the adventure, but on every other level it blows the Starter Set out of the water. And the Starter Set was pretty damn good. (My recommendation is actually to get both, if money permits - the Starter Set for "Lost Mine of Phandelver", and Essentials for everything else.)