In order to take the photograms, we used the Darkroom. A Darkroom is a special room for developing analogue (film or photosensitive paper) pictures. Inside the darkroom, there are enlargers, and chemicals for photo emulsion.
Photo emulsion is the process of immersing a picture in various chemicals (developer, stop and fix), to make a permanent image and stop the picture reacting to light. Developer is the first chemical, in the left bath. This creates an image by turning the silver halide on the film or paper into silver, but it won't be permanent. Unless stopped, the image will get darker the longer it is left to develop. Stop, in the center, neutralizes the developer, halting its reaction. The final bath has fix, which stops the reaction, stopping the image from darkening over time. During this process, we can only use red light, as the picture reacts to other colors of light and could ruin the images.
The other equipment in the room is an enlarger. Enlargers provide light and are used to make positive images by shining light through the negative film onto photosensitive paper. The dark areas of the negative block light making the corresponding areas on the paper lighter. This makes it correspond with what we can see, as negatives are darkest where light falls.