Uninterruptible Power Supply (UPS) and generator backup power sources serve the same purpose – to provide secondary power to a load during a primary power outage. However, they differ in their operation, capacity, and application. A UPS provides short-term power (typically seconds to minutes) to a load using batteries or flywheels, whereas a generator provides long-term power (hours to days) using fuel-powered engines. UPS is suitable for small to medium-sized loads, while generators are more suitable for larger loads and longer duration outages. Additionally, generators require regular maintenance, fuel storage, and exhaust ventilation, whereas UPS systems are generally more compact and require less maintenance.