Plankton is a catch-all name for the tiny lifeforms that inhabit our water. As they are the bottom of the food chain, they are essential to all life on earth. They also excrete oxygen as a waste product and perform other chemical processes that help to keep ocean waters healthy for other living things.
Dutch filmmaker Jan van IJken filmed different types of plankton through a microscope and assembled this gorgeous compilation of their forms. Some look like inanimate objects, while others resemble critters we might recognize if they were bigger. (via Geeks Are Sexy)