Earth's axis is an imaginary line that runs from the North Pole to the South Pole. This axis is tilted at an angle of about 23.5 degrees relative to its orbit around the Sun. This tilt is responsible for the changing seasons as different parts of the Earth receive varying amounts of sunlight throughout the year. As the Earth rotates on its axis, it completes one full turn approximately every 24 hours, which creates the cycle of day and night. The rotation also affects the climate and weather patterns, influencing how we experience different times of the year across the globe.