On September 9, 1947, a team of computer scientists and engineers reported the world’s first computer bug. A bug is a flaw or glitch in a system. Thomas Edison reported “bugs” in his designs as early as the 1800s, but this was the first bug identified in a computer. Today, software bugs can impact the functioning, safety, and security of computer operating systems. “Debugging” and bug management are important parts of the computer science industry.

This bug, however, was literally a bug. “First actual case of bug being found,” one of the team members wrote in the logbook. The team at Harvard University in Cambridge, Massachusetts, found that their computer, the Mark II, was delivering consistent errors. When they opened the computer’s hardware, they found ... a moth. The trapped insect had disrupted the electronics of the computer.

Among the team who found the first-reported computer bug was computer-language pioneer Grace Hopper. She is often given credit for reporting the bug, but that is not true. She was, however, the person who likely made the incident famous.

Hopper, who earned a mathematics doctorate from Yale University in 1934, was one of the first computer programmers. Hopper invented the first English-language data-processing compiler, which laid the foundation for the development of machine-independent programming languages, like COBOL that she helped develop.
 
bug
Noun

mistake or flaw in a computer program.
computer
Noun

device designed to access data, perform prescribed tasks at high speed, and display the results.
computer science
Noun

study of the design and operation of computer hardware and software, and the applications of computer technology.
consistent
Adjective

maintaining a steady, reliable quality.
deliver
Verb

to transfer or hand over.
disrupt
Verb

to interrupt.
electronics
Noun

devices or tools that use electricity to work.
engineer
Noun

person who plans the building of things, such as structures (construction engineer) or substances (chemical engineer).
error
Noun

mistake.
flaw
Noun

mistake or error.
function
Verb

to work or work correctly.
glitch
Noun

defect.
hardware
Noun

computer machinery.
identify
Verb

to recognize or establish the identity of something.
impact
Verb

to influence or have an effect on something.
industry
Noun

activity that produces goods and services.
insect
Noun

type of animal that breathes air and has a body divided into three segments, with six legs and usually wings.
inventor
Noun

person who creates a new idea, machine, product, device, or process.
literally
Adverb

exactly what is said, without exaggeration.
machinery
Noun

mechanical appliances or tools used in manufacturing.
operating system
Noun

collection of software that directs and controls a computer's overall operation. Also called an OS.
security
Noun

safety or stability.
software
Noun

electronic programs of code that tell computers what to do.
system
Noun

collection of items or organisms that are linked and related, functioning as a whole.

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    Writer

    Caryl-Sue, National Geographic Society

    Producer

    Caryl-Sue, National Geographic Society

    Last Updated

    July 15, 2020

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