Definition
Escherichia is a genus of bacteria that includes many common and harmless species. Most notably, it's known for *Escherichia coli*, or *E. coli*. While many *E. coli* strains are part of our gut flora and help with digestion, some can cause food poisoning. Think of Escherichia as a family of bacteria, some members being helpful roommates, others causing a total house party disaster in your digestive system. They're usually rod-shaped and live in the intestines of animals. In short, *Escherichia* represents a mixed bag of bacterial species.