What is the difference between a substation and a power grid?

Question

...i really hope there are as few differences as possible

Answer 1

a substation takes power from the grid and adjusts the voltage to that required by the users.  It can also put power onto the grid doing the same, adjusting the voltage to match the grid.

Answer 2

There are three main components of a power system.  The generator or source, the substation, and the load.

The purpose of the substation is to step down the voltages from the generator or power plant and also to distribute the power among different loads (homes).

When two or more power systems are connected together, that is when they form a grid.

Answer 3

Think of a substation as one node on the power grid.