Cnidarians or Coelenteratas are a phylum that contains more than 10,000 species of animals. They’re mostly made up of aquatic animals and marine environments. For a long time Cnidarians were grouped with Ctenophores in the phylum Coelenterate, but once differences were noticed over time they were then separated into different groups. These organisms are in the domain Eukaryota, the Animalia Kingdom, and the Eumetazoa Subkingdom.
P.S. My ID is in the bottom left corner. It was really dark where I was, and no flash was permitted.