Continue your tour of Lina's microbiome by surveying the five major types of microbes: bacteria, archaea, fungi, protists, and viruses. Examine what they do and where they live in the human body. The statistics are astonishing, since just over half the cells in your body are microbes, comprising some 39 trillion microbial cells versus 30 trillion human cells. Plus, we harbor 380 trillion viruses!