Salmo trutta, commonly known as the brown trout, is a species of freshwater fish native to Europe and parts of Asia. It is characterized by its brownish body, which is often adorned with dark spots. Brown trout are typically found in rivers, streams, and lakes, where they prefer cool, well-oxygenated waters. This species is an important game fish and is often sought after by anglers. Brown trout are known for their adaptability, thriving in various habitats, and can be found in both freshwater and brackish environments. They primarily feed on insects, small fish, and crustaceans, making them an integral part of their ecosystem.