The average person's skin contains around 1 trillion bacteria. The bacteria called either skin flora, skin microbiome, or skin microbiota are microorganisms which live on the skin. There are around 1,000 species which are largely found in the layers of the epidermis, the outer most layers of the skin, and hair follicles. Bacteria living on human skin are essential as they help with vitamin production, boost the immune system, and protect humans from bad bacteria called pathogens.
More about bacteria: