A cheesesteak is a popular sandwich originating from Philadelphia, made with thinly sliced beefsteak and melted cheese, typically served in a long hoagie roll. The most common cheeses used are Cheez Whiz, provolone, or American cheese. Cheesesteaks are often topped with sautéed onions, and sometimes peppers or mushrooms, adding flavor and texture. They are a staple of Philadelphia cuisine and have gained popularity across the United States, with many variations available in different regions.