The Earth experiences seasons because its axis is tilted about 23.4 degrees relative to its orbit around the Sun. This tilt means that as the Earth revolves around the Sun, different parts of the Earth receive varying amounts of direct sunlight throughout the year. When the Northern Hemisphere is tilted toward the Sun, it receives more direct sunlight leading to summer there, while the Southern Hemisphere receives less direct sunlight and experiences winter. Six months later, the situation reverses, causing opposite seasons in each hemisphere. The Earth's tilt remains pointed in the same direction as it orbits, causing this seasonal change in sunlight angle and daylight duration, which drives the cycle of seasons.