Marine life live in the water column of large bodies of water and that cannot swim against a current. They provide a crucial source of food to many large aquatic organisms, such as fish and whales. These organisms include drifting or floating bacteria, archaea, algae, protozoa and animals that inhabit, for example, the pelagic zone of oceans, seas, or bodies of fresh water. Essentially, plankton are defined by their ecological niche rather than any phylogenetic or taxonomic classification. Though many planktonic species are microscopic in size, "plankton" includes organisms covering a wide range of sizes, including large organisms such as jellyfish. The
Shrimp and prawn as food Shrimp and prawn as food Shrimp and prawn are important types of seafood that are consumed worldwide. Although shrimp and prawns belong to different suborders of Decapoda, they are very similar in appearance and the terms are often used interchangeably in commercial farming and wild fisheries. A distinction is drawn in recent aquaculture literature, which increasingly uses the term "prawn" only for the freshwater forms of palaemonids and "shrimp" for the marine penaeids. In the United Kingdom, the word "prawn" is more common on menus than "shrimp"; the opposite is the case in North America. The term "prawn" is also