You are not alone if you don’t know what forams (short for foraminifera) are, so let’s start with the basics. Simply put, forams are single-celled organisms related to the familiar amoeba that produce a hard shell. These shells look like the shells you might pick up on the beach, but they are much smaller—most are between 0.05 and 0.5 mm (about the size of a pencil tip). Forams are important organisms in their own right. They eat decomposing plants and animals, turning them into useful minerals. Forams are also a source of food for many worms, crustaceans, snails, echinoderms (like sea urchins and starfish), and fish.
Read more at the Smithsonian Institute’s Ocean Portal Ocean Blog: Story Link