Margaret Hamilton

Margaret Hamilton took a job programming weather-prediction software at MIT in 1959 to support her husband through law school. There were no courses in the subject; she learned by doing. By the mid 1960s she was at the MIT Instrumentation Laboratory, which had the contract to write the software for the Apollo guidance computer, and she eventually led the team responsible for the on-board flight software.

She often brought her daughter Lauren to the lab at weekends. One day the four-year-old, playing with the simulator, selected a pre-launch program during a simulated flight and crashed it. Hamilton wanted to add protection against an astronaut doing the same. NASA told her astronauts were trained not to make mistakes. On Apollo 8, one did exactly that, and the crew had to spend hours reloading data. After that, the protection went in.

She was also insistent that the software should prioritise its tasks and recover from overload. Three minutes before Apollo 11 touched down in July 1969 the computer began throwing alarms because a radar was flooding it with data. Because of the priority scheduling, it dropped the low-priority work, kept the landing running, and Neil Armstrong was cleared to continue.

She coined the term software engineering to make the case that her discipline deserved the same respect as the hardware. In 2016 she received the Presidential Medal of Freedom.