Jō is a long stick that people use in a type of martial arts called "jōdō". It's a bit like a big pencil that you can hold with both hands. The stick is usually made of wood and it's about 3-4 feet long.
In jōdō, people use the jō to defend themselves and sometimes they use it to hit their opponent. It's a very special way of fighting and it takes a lot of practice to get good at it.
To use the jō, you have to learn some special moves. Some moves involve holding the jō with one hand and some involve holding it with two hands. Sometimes you have to twist your body and sometimes you have to jump or duck.
Jōdō is a very fun sport to watch and it's even more fun to try it yourself. It's important to learn how to use the jō safely, so it's best to learn from someone who knows what they're doing. Overall, jō is a neat stick that people use to practice a really cool type of martial arts.