An uninterruptible power supply (UPS) is a device that provides backup power to electronic equipment when the main power source fails. It ensures that devices like computers, servers, and medical equipment continue to operate without interruption, protecting them from data loss and damage. A UPS typically contains a battery that kicks in instantly when it detects a power outage. In addition to providing backup power, a UPS also offers surge protection, which helps safeguard connected devices from voltage spikes. This is particularly important for sensitive electronics, as it can prevent costly repairs and data corruption. Overall, a UPS is essential for maintaining the reliability of critical systems.