Lavalier Microphone

A lavalier clips at around sternum height, six to eight inches below the mouth, wired to a recorder or feeding a wireless transmitter in a pocket. It travels with the speaker. The distance to their mouth never changes and the level stays even however much they move.

Most are omnidirectional, which means they pick up the room along with the voice. The usual failure is clothing rustle. Tape the cable and keep fabric off the capsule and it goes away.