The document discusses the rotation and revolution of the Earth. It begins by asking questions about what causes day and night and how long it takes Earth to revolve around the sun. It then provides details that the Earth rotates on its axis every 24 hours, causing days, and revolves around the sun every 365.25 days, causing a year. Rotation is defined as the turning of Earth on its axis, which causes both day and night and apparent motion of stars in the sky. The revolution of Earth around the sun takes one year or 365.25 days to complete.