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It is clear after only minimal observation that objects change their position in the sky over a period of time. This motion is conveniently separated into two parts:
1. The entire sky appears to turn around the north and south celestial poles once in 24 hours. This is termed the daily or diurnal motion of the celestial sphere, and is in reality a consequence of the daily rotation of the Earth on its axis. The diurnal motion affects all objects in the sky and does not change their relative positions: the diurnal motion causes the sky to rotate as a whole once every 24 hours. The top right figure illustrates diurnal motion around the north celestial pole.
2. Superposed on the overall diurnal motion of the sky is "intrinsic" or "proper" motion that causes certain objects on the celestial sphere to change their positions noticeably with respect to the other objects. These were called "wanderers" by the ancient astronomers. They include the planets, the Sun, and the Moon. In reality all objects on the celestial sphere "wander" (see the right panel) but for most the motion is so slow that we can consider them to be fixed in relative position, leaving the planets, Sun, and Moon to wander with respect to them.
Animation: diurnal and proper motion for stars
Animation: diurnal motion on the celestial sphere