During suspend most devices are shutdown, and system state is saved
in RAM. The system still requires power in this state. Most modern
systems require 3 to 5 seconds to enter and leave suspend, and most
laptops can stay in suspend mode for 1 to 3 days before exhausting
During hibernate the system is fully powered off, and system state
is saved to disk. The system does not require power, and can stay
in hibernate mode indefinitely. Most modern systems require 15 to
45 seconds to enter and leave hibernate, and entering and leaving
hibernate takes longer when you have more memory.
Hybrid-suspend is the process where the system does everything it
needs to hibernate, but suspends instead of shutting down. This
means that your computer can wake up quicker than for normal
hibernation if you do not run out of power, and you can resume even
if you run out of power. s2both(8) is an hybrid-suspend
I guess the difference here is that the system state saved to Disk (and not RAM) , but the system is not full shutdown (like hibernate) but suspend instead.