Microbes, or microscopic organisms, are everywhere. Bacteria are one type of microbe, and probably the one we have heard about or read about in books. We often think of bacteria as germs, or something that will make us sick. While there certainly are bacteria that can infect us and cause sickness (i.e. strep throat, food poisoning, tuberculosis), many bacteria are beneficial and important for our survival and the survival of the world around us. For example, we have nearly 1000 species of bacteria living in our digestive tract, helping us break down and utilize nutrients from the foods we eat, helping to prevent infections, making vitamin K and more! We even use bacteria to make foods like yogurt, sauerkraut, cheese, and pickles to name a few. Bacteria make up their own kingdom that goes by the same name. Another kingdom, Archaea, is quite similar to bacteria and was once part of their kingdom. It wasn’t until the 1970’s that they were actually separated into their own kingdom. Archaea and bacteria differ in the structure of the cell wall; the cell wall of archaea offers more stability in extreme conditions such as high pressure, salinity or temperature. So archaea are considered “extremophiles” that can survive where other organisms cannot.