Why do we have different time zones?

Why do we have different time zones?

             The earth rotates on its own exis due to this rotation, different parts of the earth receive different amounts of sunlight.

thus, causing morning, noon, evening and night.

  Now, if we had one time zone, then 12pm would be noon at some places but it would be night or evening at other places which would be inconvenient.

 Hence, scientist made different time zones according to the earth's rotation with respect to the sun.