Sunlight refers to the light and heat emitted by the sun. It is a form of solar radiation that travels through space and reaches the Earth's atmosphere, where it is scattered or absorbed by various materials such as clouds, water vapor, ozone, etc., before reaching the surface. Sunlight plays an essential role in sustaining life on earth, providing warmth and light necessary for plants to grow and animals to thrive. It also has numerous benefits for humans including promoting vitamin D production which is crucial for bone health, improving mood through exposure to natural light, and boosting energy levels.