"First actual case of bug being found," according to the brainiacs at Harvard, 1945. The engineers who found the moth were the first to literally "debug" a machine.
Photograph courtesy Naval Surface Warfare Center, Dahlgren, Virginia

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    On September 9, 1947, computer scientist Grace Hopper reported the world’s first computer bug. A computer bug is a mistake in the system. 
    Grace and her coworkers at Harvard University were having trouble with their computer. They did their work over and over, but found the same little flaw. Engineers, including the inventor Thomas Edison, had always called little flaws in machinery “bugs.” 
    Grace’s coworkers opened up the computer’s machinery, called hardware. Inside all the wires, they found . . . a moth! The moth had accidentally flown in and got trapped between parts of the big computer. Grace and her friends thought it was funny that the “bug” was actually a “bug”!
  • Term Part of Speech Definition Encyclopedic Entry
    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


    flaw Noun

    mistake or error.

    function Verb

    to work or work correctly.

    glitch Noun


    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.