A USB microphone is an external audio input device that captures sound and sends it to software for processing. Because it connects through USB, it is easy to add to a Raspberry Pi, laptop, or embedded system and is often used for voice input, speech analysis, or environmental monitoring.
In cyber security, a USB microphone matters because it expands the attack surface with a live sensor. If a device records audio, security teams need to consider permissions, local versus remote processing, storage of clips or logs, and who can access the data. In attacks, a microphone can be abused for covert listening or for collecting speech that may reveal passwords or private activity. In defenses, the same hardware can support monitoring systems, but it should be locked down, updated, and configured to minimize unnecessary collection.