Escherichia Coli, also known as E. Coli is one of the most commonly studied bacterium species in the world. Their culture is very inexpensive to grow in a lab. They usually live in the lower intestines of a warm-blooded animal such as humans. Most types of E. Coli are harmless while some may lead to serious diseases. Many scientists who study genetics and microbiology use E. Coli as the host animal for their studies. They have the iconic pill shape and usually smaller than 10 micrometers. In the following images, they are marked with white arrows for easier identification of E. Coli. While the arrows are pointing to the larger of the bacteria, many other smaller bacteria are also visible in the background. A short video is also added to show the movements of these impressive beings.