What are the main differences between gi and nogi Brazilian Jiu-Jitsu?
In Brazilian jiu-jitsu with a gi you wear the funny Asian pajamas. In no-gi Brazilian jiu-jitsu you wear shorts and usually a t-shirt or rash-guard top. You can grab onto the funny pajamas but you can't grab onto any clothes in no-gi.
The gi absorbs sweat, adds friction, and provides a wide variety of grips to choke, throw, and control from. Often the rules in no-gi are more permissive, particularly with regards to leg locks. Brazilian jiu-jitsu with the gi has more carry-over from judo. Without the gi there is more carry-over from modern and Catch wrestling. Wearing the gi is more traditional. Playing without the gi has more applicability to mixed martial arts.
Both are applicable to self-defense. Both are valid jiu-jitsu.
"Gi" refers to the uniform that is worn during most martial arts practice. Nogi means that you do not wear one, and instead wear shorts or spats and a rash guard or you are shirtless.
There are a few differences when talking about gi vs. nogi when executing techniques.
- Gis provide friction that may make it easier OR harder to escape or change positions.
- Gis give you the opportunity to grab onto you opponent or yourself with stronger grips.
- Wearing a gi lets you show off you belt(seriously though, your belt/opponent's belt can be used as a handle)
- Give's you the opportunity to practice grips for self defense situations(most likely your attacker will not be wearing a gi. If you see someone get mugged by someone who is wearing a gi, tell me!)
- Rash guards/bare skin provide less friction than gis do and can actually be slippery, which may help with some escapes.
When referring to competition, there are a few variations between gi and nogi.
- Some submissions or sweeps/throws may not be legal for gi but will be nogi (i.e. scissor takedown, heel hook).
- It is against the rules to grab onto clothing in nogi, whereas nogi grips are still legal in gi competition.
- Gi competitors are divided based on belt, nogi competitors are divided based on what belt they would be wearing,, or how long they have been doing BJJ.
All in all, nogi tends to be harder in general, because your opponent is slippery and hard to grab. However, nogi concepts translate better into self defense, since it gives a more realistic representation of what people outside the gym might wear. Also, nogi techniques can always be done with a gi on, whereas vice-versa is not true. If you are starting out BJJ, try to pick one or the other and then transition to both later on. I do believe that it will only be beneficial to your BJJ skills to train in gi and nogi.