The IBM 4020 Military Computer – Tracking Missiles with 6-bit Bytes | The CPU Shack Museum

Back in the late 1950’s two things were happening (ok more then 2 but 2 relevant to todays discussion) the military was looking to replace the new but now already out of date tube based SAGE and AN/FSQ-7 Strategic Air Command (SAC) computers, and multiple bits of data were beginning to be called bytes. The SAC was in charge of all of the US’s Strategic bombers, ICBMs, and detecting/tracking the threats of bombers/ICBMs from the USSR. The older tube based SAGE computer was designed for relaying, consolidating, and displaying data from Early Warning RADARs across North America to paint a situation picture of what was going on. It worked fine, for bombers, but the late 1950’s also brought about ICBMs, and ICBMs are much much faster then mere bombers. The SAGE, and the AN/FSQ-7 lacked the processing speed to keep up with the changing data from a RADAR track of an ICBM so something faster was needed.

Source: The IBM 4020 Military Computer – Tracking Missiles with 6-bit Bytes | The CPU Shack Museum