What Is The Difference Between Japanese and Brazilian Jiu Jitsu?
BJJJ is not violent. It's actually quite the contrary. It is difficult. It will teach you the discipline required to excel at your chosen field.
BJJ was initially designed as a self defense method. However, MMA is clearly the winner of this debate. BJJJ will be incorporated into your MMA training, which means that even beginners will have more ground skills than the average person.
BJJJ is more effective than Karate for self-defense because its techniques are more practical. Although Karate is a good martial art, the modern practice tends to be too focused on point fighting and light touch.