Methods of self-defense
There are three main methods to defend oneself against an attack. Various styles of martial arts have been developed to exploit each method.
The three methods
Meet the attack with force
This method uses strikes such as blocks, punches, and kicks to forcibly repel the attack. It uses medium to close range fighting and limited throws. It rarely uses locks or submission holds. Examples are taekwondo, karate, boxing, and other striking arts.
Greet and engage the attack
This method uses mainly throws, takedowns, pins, and submission holds. It uses close-range fighting and limited punches and rarely uses kicks. Examples are judo, wrestling, MMA, and other grappling arts.
Retreat from the attack
This method uses avoidance, locks, and throws. It uses medium to close range fighting and rarely uses punches or kicks. Examples are aikido, jujutsu, and other avoidance arts.
While each of these methods may be useful under the right circumstances, they are mutually exclusive. For example, it is difficult to grapple and strike at the same time, to avoid and grapple at the same time, or to strike and avoid at the same time.
Avoid mixing the methods
Martial artists are people who study a martial art. Most study one art exclusively, but some may also try a different art, usually one from the same method as their original art. For example, a taekwondo practitioner may also study karate. By staying within a specific method, the student learns ways to respond to almost every conceivable attack. However, when a student studies a martial art from a different method, problems may arise. In a surprise attack on the street, you must react instinctively or reflexively since there is no time to think consciously about a defense.
If you are a student of a striking art, you will instinctively block and counterattack. If you are a student of a grappling art, you may duck and tackle, or grab and throw. If you are a student of an avoidance art, you will probably step to the side and flip the attacker. If you are also studying a martial art from a different method, what would you do? You would probably do some half-ass, ineffective combination of the two arts and get your butt kicked.
A martial artist who has specialized in one method of self-defense will not make the mistake of being seduced into another method of fighting. For example, a taekwondo specialist who gets suckered into grappling with a grappler will probably lose, or a grappler who tries to punch it out with a boxer will probably get butchered. A well-trained martial artist will attempt to seduce an opponent into fighting in his or her method of fighting while exploiting weaknesses in the attacker's method of fighting.