The human microbiome is the collection of microbes that benefit human society, providing services such as bioremediation and assisting in food production the collection of microbes that share the same environmental requirements as human the collection of pathogenic microbes that attack humans and cause disease the collection of microbes important for the functioning of the ecosystem, such as photosynthetic and nitrogen-fixing bacteria the collection of symbiotic microbes living on or within the human body, often performing functions that humans do not possess.