what was the forerunner of the modern camera and what was it mostly used for?

Camera obscura was the forerunner of the modern camera, a dark room ( or box) with a small hole in one side, through which an inverted image of the view outside is projected onto the opposite wall, screen, or mirror, and then traced.

The camera obscura was used as a means to study eclipses without the risk of damaging the eyes by looking into the sun directly. It was also used as an aid for drawing or painting.