The Greyhound is a breed of sighthound that has been primarily bred for coursing game and racing but with recent resurgence of popularity as a pedigree show dog and family pet. It is a gentle and intelligent breed. A combination of long powerful legs deep chest flexible spine and slim build allow it to reach average race speeds of or in excess of 18 metres per second (59 feet per second) or 63 kilometres per hour (39 mph).