where exactly spritebatching and using spritesheet technique differs in draw calls and gpu processing?

Question

I used to create games in cocos 2d engine and to optimise the draw calls,I use texture packer tool to make sprite sheets and using that i optimised draw calls,but later I saw approach called sprite batching.But in terms of draw calls both sprite batching and spritesheet are giving me same result,but what exactly the difference in terms of game performance with sprite sheet technique and spritebatching

Does it effect gpu network difference?