The Rottweiler (/ˈrɒtwaɪlər/, UK also /-vaɪlər/) is a breed of domestic dog, regarded as medium-to-large or large. The dogs were known in German as Rottweiler Metzgerhund, meaning Rottweil butchers' dogs, because their main use was to herd livestock and pull carts laden with butchered meat to market. This continued until the mid-19th century when railways replaced droving. Although still used to herd stock in many parts of the world, Rottweilers are now also used as search and rescue dogs, as guard dogs, and as police dogs. Obedience training and socialization are required. The portrayal of Rottweilers as vicious or malevolently aggressive dogs in several fictional films and TV series, most notably in The Omen, along with sensationalist press coverage, has created a negative image of the breed. In the UK, Rottweilers are widely perceived as status dogs – potentially dangerous or aggressive dogs kept to intimidate others, and possibly as weapons.