Direct sunlight refers to sunlight that reaches the Earth's surface without being obstructed by clouds, buildings, or other objects. This type of sunlight is strong and can cause shadows to be sharp and well-defined. It is essential for processes like photosynthesis in plants and helps regulate the Earth's temperature. When exposed to direct sunlight, surfaces can heat up quickly, and it can also lead to sunburn on human skin. The intensity of direct sunlight varies based on factors such as time of day, season, and geographic location. For example, areas closer to the equator receive more direct sunlight throughout the year compared to regions like Antarctica.