The difference between a habitat and a niche is that a habitat refers to the physical environment where an organism lives, while a niche describes the role or function an organism plays within that habitat. The habitat provides the necessary resources for survival, such as food, shelter, and mates. In contrast, the niche encompasses how an organism interacts with other species, its specific contributions to the ecosystem, and its adaptations. Understanding both concepts is crucial for studying biodiversity and ecosystem dynamics.