What is the main feature of a UPS that distinguishes it from other power sources?

The distinguishing feature of an Uninterruptible Power Supply (UPS) is that it continues to operate during a power interruption. This capability is critical for ensuring that connected devices, such as computers and medical equipment, remain operational when there is a power failure. A UPS provides a backup source of power, typically via batteries, allowing users to save their work, safely shut down devices, or maintain critical operations without interruption.

While some alternatives to a UPS may offer portable or low-maintenance options, they typically do not provide the same level of power management during outages. The nature of a UPS is specifically designed for reliability in emergency power situations, making it indispensable in settings where continuous operation is necessary.