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September 6, 2017

70 years since the discovery of the first computer bug

Chaos theory, as commonly recounted, goes something like this: a butterfly flaps its wings and it can cause a typhoon halfway around the world.

This, of course, is a gross simplification of chaos theory and what is deemed the “butterfly effect,” but almost 70 years ago, a moth did change the world of technology, and this is why we are celebrating Bug Day.

Grace Hopper in history

Grace Hopper joined the US Navy Reserve in 1943, and a year later was promoted to lieutenant and stationed at the Bureau of Ordnance Computation Project at the Cruft Laboratory at Harvard University. She was the third person to ever program the massive Harvard Mark I computer, and coauthored three papers on the computer along with the Lab’s head, Howard H. Aiken.

Discovering a moth

In 1947, an upgraded computer model was completed, the Mark II. This new shiny machine was 2.6x faster than the Mark I, and had electromagnetic relays instead of the electromechanical counters that were used in the Mark I. On September 9th, 1947, Grace Hopper found the first actual computer bug. A moth was stuck between relays of the Harvard Mark II computer, and she documented this finding in her log book. The notion of bugs was described in other fields previously, but the moth discovery was the first use of the term ‘debugging’ in the field of computers.

Celebrate Bug Day with us

In honor of Bug Day, we’ll be sharing some of the most critical computer bugs in history throughout the month of September. Stay tuned @bugsnag to read about:

We’re also holding a celebration in our office in San Francisco. You can find the details here.

We celebrate this and all the contributions Grace Hopper has made on the 70th anniversary of the moth discovery with Bug Day.


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