It has long been known that bacteria, viruses, and eukaryotes
such as fungi and arthropods inhabit the skin. However,
the community of microorganisms on human skin is
more complex than once thought. Understanding the composition
of the skin microbial community is a significant
advance from older classifications of cutaneous microbiota
that focused on skin microbes only as pathogens or opportunistic
pathogens, and has come from the development of
methods based on sequencing technologies that are independent
of the need for cultivation of microbes. This new
information has revealed that the composition of the skin
microbiome is diverse and loosely organized and varies for
different skin locations. Most importantly, more recent
descriptions of the composition of the skin microbiome
have inspired new work towards understanding the functional
significance of resident microbes on the skin, and
have led to important new advances in our understanding
of both normal physiology and disease.