unit 1: out of the darkness...

The term "Camera Obscura" literally translates to "dark room", and the use of a pinhole in a window shade to form an inverted image of an outside scene on an wall of a dark room has been known since at least the 6th century. The replacement of the pinhole with a lens was first described in scientific journals in 1568. 

Thusly did the camera obscura become a solution in search of a problem.  It was in the early 1800's however that two Frenchmen; Jospeh Nicephore-Niepce and Louis Daguerre, and an Englishman; Henry Fox-Talbot, began experiments independently of one another to "fix the shadows" of the camera obscura image permanently onto a surface.

Daguerre gets credit for the first successful image, and Talbot's process is the antecedent of todays silver-based photography. And although neither could have fathomed the impact their discoveries would have on the generations which followed, both saw a rapid and exponential growth of the medium throughout their lifetime.

For more information see:
Daguerreotype                                                           Calotype