For additional meanings of "Baker", please see Baker.
A baker was someone who was employed in a bakery, where they made and sold various types of baked food, including bread.
In Rurigan's holographic village, Depnen was the baker. He baked greenbread. (DS9: "Shadowplay")
In another holoprogram set in 1944 France, Neelix was a baker in Sainte Claire. (VOY: "The Killing Game")