Bacteria are microscopic, single-celled organisms that are found almost everywhere on Earth. Commonly just known as "germs" which make you sick, bacteria are actually essential to life on earth. Bacteria have a wide variety of different functions, from breaking down dead organic matter to producing oxygen to producing medicine to digesting the food in your body. By numbers alone, there are far more bacterial cells in your body than human cells!
Although virtually every bacterium is far too small to see with your eyes, bacteria often grows to form large bacterial colonies which can be seen. Often this happens places we don't want it to, like on food or drink which has been stored improperly. However, some beneficial bacteria grows in the wild to form natural phenomena that usually looks like a strange slime. While rare in the Western world, some of these bacterial jellies are actually eaten! While being a far cry from being related to any plant in any way, these bacteria are usually considered to be a vegetable for culinary purposes.