Usually available on higher-end devices, a zoom microphone provides increased audio quality by focusing sound collection on the subject being recorded, directing its aim as you zoom in with the camera lens.
Regular microphones normally capture sounds from various directions, producing an audio experience that is not as well matched with the image as a zoom microphone can provide. That being said, it all depends on your intention with a video. For instance, a zoom microphone is less likely to capture the voice of the person shooting the scene, as well as omnidirectional sounds that you may not want to be recorded. Consequently, a zoom microphone can be a fitting solution to record distant sounds, meetings, lectures, and presentations.