The sailor's hornpipe is a type of dance that sailors used to do on board ships to entertain themselves and pass the time. It's called a hornpipe because it used to be danced to music played on a type of musical instrument called a hornpipe.
During the dance, the sailor would do lots of different movements with their feet, spinning around and kicking their legs out. It's a bit like a jig or a reel that you might see people doing in Irish dancing.
The dance is usually done in a special outfit, which includes a jacket, trousers, and a hat. The outfit is often decorated with stripes, which were supposed to represent the sailor's rank on board the ship.
Today, the sailor's hornpipe is still performed by people who are interested in traditional dance and music. You might see it at a folk festival or other cultural events. But even if you don't see the sailor's hornpipe being performed in person, you can still find videos of it online to watch and enjoy.