Bartitsu is like a bunch of different fighting styles mixed together to make a cool new way to defend yourself. It was created a very long time ago in England when people wanted to learn how to protect themselves, but didn't want to just use one way of fighting like punching or kicking.
So, they took some moves from boxing, some from wrestling, and even some from Japanese martial arts called jiu-jitsu and put them all together. It's like making a recipe for a yummy cake, but instead of ingredients like sugar and flour, they used moves like blocking, throwing, and choking.
People who learned bartitsu could use it to defend themselves if someone else tried to hurt them. It was super popular back then, but not as many people practice it now. But if you want to learn how to protect yourself using all kinds of different moves, bartitsu might be the perfect thing for you to try!