What is the difference between Orion and the Orion nebula?

Orion is a constellation made up in the minds of the ancients to represent "Orion" a hunter in mythology.

The Orion Nebula is a diffuse nebula located south or Orion's belt. It is an area of extensive star formation.

It is only called Orion Nebula as it is seen within the constellation of Orion.

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