Notorious software bug was killing people 40 years ago — at least three people died after radiation doses that were 100x too strong from the buggy Therac-25 radiation therapy machine

Software bugs can cause a lot of anxiety, inconvenience, and leech away valuable time, but thankfully they are rarely fatal. However, back in 1985 a radiation therapy machine called the Therac-25 was only just getting started on its human killing spree. There was a bug in its software which resulted in a deadly race condition, and at least six unfortunate individuals received doses of radiation that were 100x too strong. Three people died as a result of this software bug.

When launched, Therac-25 was an…