"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 bug is a flaw or glitch in a system. Thomas Edison reported “bugs” in his designs as early as the 1800s, but Hopper was the first to identify one in a computer
    In Hopper’s case, it was literally a bug. Her coworkers at Harvard University in Cambridge, Massachusetts, found that their computer 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. 
    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.
  • 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.