SAGE (Semi-Automatic Ground Environment)

SAGE, or Semi-Automatic Ground Environment, was a United States early-warning system developed in the 1950s to detect and respond to incoming enemy aircraft or missiles. It integrated radar data from multiple sites, processed information in real-time, and helped military operators track potential threats across a wide area. Using computers, SAGE provided near-instantaneous updates and coordinated defense responses, such as guiding interceptors. This system was a pioneering step in real-time military data processing, combining automation with human oversight to improve national security during the Cold War era.