Suspend puts the computer to sleep by saving system state in RAM. In this state the computer goes into a low power mode, but the system still requires power to keep the data in RAM.

Is Linux suspend same as sleep?

Sleep (sometimes called Standby or “turn off display”) typically means that your computer and/or monitor are put into an idle, low power state. Depending on your operating system, sleep is sometimes used interchangeably with suspend (as is the case in Ubuntu based systems).

Is it better to suspend or hibernate?

TL;DR. Suspend saves its state to the RAM , hibernation saves it to disk. Suspension is quicker but doesn’t work when running out of energy, while hibernating can deal with running out of power but it is slower.