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.
So, too, can sea anemones. They are close relatives of jellyfish and corals and bear similar stinging tentacles. Some sea anemones move around freely, and some hitch rides on the backs of crabs, but most anchor their backsides to rocks and then wave their tentacles around to sting and eat passing prey.