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Tester's Day

Tester's Day commemorates the day in 1947 when the first actual bug was found in a computer—and by actual bug, we mean real and once-was-living bug. Scientists at Harvard University had been working on the Mark II Aiken Relay Calculator when they found a moth stuck between the two solenoid contacts of the electromechanical relay. The moth had shorted out the relay. Some say Grace Hopper found the bug, while others say it was William "Bill" Burke or another scientist. One of the scientists working on the computer, originally thought to have been Hopper, taped the moth into the computer's logbook and labeled it with the note, "First actual case of bug being found." Being that it specified "actual," it seems to imply other types of computer bugs had already been the norm. Nonetheless, it was Hopper and the other scientists she worked with who helped popularize the terms "bug" and "debug," which became standard language for computer programmers soon afterward.

"Bug" had long been an engineering term. Way back in 1878, Thomas Edison had written a letter using the term, in which he said:

It has been just so in all of my inventions. The first step is an intuition, and comes with a burst, then difficulties arise—this thing gives out and [it is] then that "Bugs"—as such little faults and difficulties are called—show themselves and months of intense watching, study and labor are requisite before commercial success or failure is certainly reached.

The word appeared in other locations following this, including in Webster's Second International Dictionary in 1934. In current times, a computer bug can be defined as a problem with a computer program or system which causes an incorrect or unexpected result. Bugs usually come from errors in the source code or the program's design, or in components or operating systems that are used by the programs. Some bugs are caused by compilers. The effects of bugs may be minuscule, or they may make a computer crash or freeze. There are also security bugs that may allow a malicious user to gain access. "Debug" dates to at least 1945 when it referred to issues with aircraft engines. Debugging now describes the process of identifying and eliminating computer bugs. It seems apparent that the name of today's holiday is Tester's Day because software testers are those who look for bugs. The day is dedicated to Grace Hopper and all other software testers.

How to Observe Tester's Day

Here are a few ways to celebrate Tester's Day:

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