Definition - What does Suspend Mode mean?
Suspend mode is a low-power computer setting that helps reduce electrical power consumption by shutting down devices that are not in use. Most laptops automatically enter suspend mode when the system runs on batteries or the lid is closed. This status is often signaled by a pulsing LED-powered light.
Suspend mode is also known as sleep mode, standby mode or power save mode.
Techopedia explains Suspend Mode
The latest standard for power management is advanced configuration and power interface (ACPI), which provides a backbone for sleep and hibernation in computers. The suspend mode in computers generally corresponds to ACPI mode S3. The absence of ACPI restricts the turning off monitors and spinning down of the hard drive.
Windows 2000 and higher versions support the suspend mode at the operating system level without the need of special drivers. The fast sleep and resume feature of Windows Vista saves volatile memory contents to the hard disk before entering suspend mode.