This is a dying art form.

Darkroom photography is painting with light. 

There is no computer, no photoshop, no printer or ink used whatsoever. These are Analog Photos developed in chemicals and toned with Selenium or Gold, Iron Carbon and Sulphur.
And sometimes a combination of variations of either of these.  

Creating the image is done using a negative that's placed into an enlarger and projected onto light sensitive paper made of silver gelatine imaging salts.
Silver bromide combined with Silver chloride - which become reduced into silver metal when exposed to light.

The process is like holding a marshmallow over a fire and toasting it either dark brown to black or light gold to yellow or grey.

In the end the paper is soaked for about an hour in water and then hung up to dry like wet clothes.