The earth rotates on its axis, bringing about day and night. A solar day or an apparent day is a period of 24 hours, the time taken for an observer at any one point on the earth to be again in the same position relative to the sun.
how do day and night explain?
By day we do things by night we settle down and sleep. Also the sun orbits around the moon.
Day is when sun rises, we don't use the light, night is dark, so we must use any of light, if no, we see nothing. Such is the different between day and night, so at the daytime we work or do some activities, but at night, we sleep,as we need it in order for our body having a relax.