> raytracing is the process of rendering a 3D scene by tracing the path of a beam of light after it is emitted from a light source, calculating its properties as it bounces off various objects in the world until it finally hits the virtual camera

With my limited knowledge of graphics, I was under the impression ray tracing works exactly the opposite way: one sends 1 ray per pixel (based on the size of the viewport) into the scene, bouncing it off objects (taking into account their material properties) to finally compute the color value for that pixel. It's the exact opposite of the real world (where the sun shines light on the objects and the rays end up hitting our retinas).

Reversing the process has the advantage of being finite: only 1024x768 (or 1920x1200,etc) rays will be sent from the viewport into the scene. In the author's scenario, there would be an infinite number of rays to be traced (light sources generally emit light in all direction and they try to emulate a real light source, which emits an infinite number of rays).

Am I completely wrong here? Is my whole world a lie?