Bug is an error, fault, or defect in software or equipment.

It is the universally used term to describe unexpected or incorrect behavior in a computer program, plugin, or hardware design.

A bug can cause anything from minor problems (like a button that doesn't work) to serious failures (like the program closing on its own or corrupting a file).

When developers release software updates, they are often for "bug fixes", that is, to fix the errors that were found in the previous version.

Another Meaning in Audio

In a more specific and less common sound recording context, the term bug can also be used as slang for a contact microphone, which is a microphone that picks up sound through the vibration of solid surfaces.