360-degree cameras capture completely panoramic images and videos.
The cameras may consist of multiple lenses or a single lens. Multi-lens cameras capture footage that has to later be stitched together and that may produce stitching artifacts. Single-lens cameras don't, but are limited in how much footage they can capture vertically. Multi-lens don't have this limitation and can go as far as capturing completely spherical footage.
Other important criteria to consider include image quality and resolution, how many microphones the camera has and where are they positioned, whether the camera has a headphone jack, if it works over wi-fi and whether it can be mounted.