A third level can be defined to identify a particular host server at the Internet address. In our example, www is the name of the server that handles Internet requests. (A second server might be called www2.) A third level of domain name is not required.
Sea anemones are a group of water-dwelling, predatory animals of the order Actiniaria. They are named for the anemone, a terrestrial flower.Sea anemones are classified in the phylum Cnidaria, class Anthozoa, subclass Hexacorallia. sea anemone is a sessile polyp attached at the bottom to the surface beneath it by an adhesive foot, called a basal disc, with a column-shaped body ending in an oral disc.
Starfish are marine invertebrates or echinoderms in the class Asteroidea. Scientists, therefore, prefer to call them sea stars. There are 1,800 to 2,000 species of sea stars that vary in size, color and other characteristics. We think of the sea star with five appendages, but some sea stars can have many more arms.