Margaret Hamilton (born on August 17th 1936) is an American computer scientist, who was one of the first computer software programmers - she even created the term ‘software engineer’ to describe what she did. She is most well-known for leading the team which programmed the computer code for the command and lunar modules used on Apollo missions to the Moon in the late 1960s and early 1970s, when she was only in her early 30s. She basically helped land a spacecraft on the Moon!
However, it wasn’t all smooth rolling. On July 20 1969, 3 minutes before Apollo 11 was due to land, the normal mission sequences were interrupted by 1201 and 1202 alarms, announcing to the astronauts that there was a hardware-related problem, but the software was trying to adjust for it. Fortunately, Margaret had programmed the computer to focus on the main objective - landing the spacecraft - and ignore other lower-priority issues. Thanks to this, instead of aborting the landing and mission, the astronauts safely landed on the moon!
For future missions, the initial designs and solutions that Margaret and her team created were kept, and her team proceeded to create software for Skylab, the first space station in the 1970s. Margaret went on to found two software companies which continue to spark ideas which improve software design and development.