Why is it light during day and dark in night?

Daylight occurs because the Earth rotates on its axis, allowing different parts of the planet to receive sunlight as it orbits the Sun. When a location on Earth is facing the Sun, it experiences daylight, while the opposite side is in shadow, resulting in nighttime. The tilt of the Earth's axis also affects the angle and intensity of sunlight, contributing to variations in day length and brightness throughout the year.