Acidithiobacillus ferrooxidans is by far the most widely studied of all extremely acidophilic prokaryotes. While it is found in many types of natural low-pH environments in a variety of geoclimatic contexts, it has been more widely cited in anthropogenic (mostly mine-impacted) environments. It is responsible for accelerating the oxidative dissolution of sulfide minerals, causing the generation of polluting acidic metal-rich drainage waters but also facilitating the recovery of base and precious metals from mineral leachates. It can colonize barren mineral landscapes, is a driver of ecological successions in acidic biotopes, and is an important model organism in astrobiology. It catalyses the dissimilatory oxidation of iron, sulfur, and hydrogen, and the reduction of iron and sulfur, and has a major impact in the geochemical cycling of these elements in low-pH environments. This infographic summarizes the fundamental phylogeny, physiology and genomic features of this extremophile.