Where did the term “bug” come from? 🐞

“Bug” in computing comes from actual insects interfering with early hardware. The most famous incident: in 1947, engineers working on the Harvard Mark II relay computer found a real moth stuck in a relay, which caused a malfunction. They taped it into their logbook with the note: “First actual case of bug being found.”

But the word bug was used in engineering before that. Thomas Edison used it in the late 1800s to describe mechanical or electrical faults:

“It’s not the machine’s fault, it’s a bug in the system.”

So the Mark II story didn’t invent the term; it just made it iconic in computing culture.

In short:

- Origin: 19th-century engineering slang for glitches.
- Popularized in tech: 1940s, after the literal moth incident.
- Meaning today: Any flaw, defect, or unintended behavior in software or hardware.

It’s a perfect metaphor: small, annoying, hard to find, and capable of breaking big systems.