Suspend Mode: (this is sometimes referred to as “sleep mode”)
The computer disconnects from any networks, tells everything to pause, and removes power from everything except RAM.
So, you put your computer into a state where the memory of what was going on in every program is still present, but the computer is, essentially, off.
However, because RAM still needs to be powered, there is a little power drain, even when your computer is suspended. Of course, this is almost negligible.
Suspend is quite useful and laptop users use it all the time.