A Saiyajin, is a being from Planet Vegeta, though many were alive before Friezas rain of terror, only Goku, Nappa, Radditz, and Vegeta survived. The Saiyajins have black hair that is spiked up, black eyebrows, and evil eyes. All Saiyajins that are evil share a desire for extreme action. They also gain higher power levels after being near to death.
That level can only be reached by Saiyajins that stil have their tails. To transform to Oozaru they only have to look at the full moon. An Oozaru looks like a giant ape. The Powerlevel is increased by 10.
This form is first reached by Goku in the Freezer saga. This form can only be reached with a high Powerlevel and you must be really angry. A Super Saiyajins Hair gets longer and golden. The eyebrows get also golden. Muscles increase damaticaly. A SSJ is sometimes accompanied by an golden aura.
This is a stage beetween SSJ and SSJ 2. The mass encreases dramatically. Muscles buggle up. You have a very high Poverlevel but your speed decreases very strong. This stage is first reached by Trunks.
Super Saiyajin 2
This form was reached first by Gohan in the Cell Saga. SSJ 2 has a huge power and speed increasion. Hair gets even longer than SSJ. Muscles get bigger. The aura has lightnings in it.
Super Saiyajin 3
This stage was only reached by Goku and Gotenks in the Boo Saga. Your Powerlevel and speed increase very dramaticaly. Muscles buggle up. Hair reaches to the feet. Eyebrows dissapear.
This form is the same like Oozaru but it is stronger and has a golden fur. You have to be SSJ to turn into a Golden Oozaru. Powerlevel is encreased by 20.
Super Saiyajin 4
This form is reached out of a Golden Oozaru. It's the strongest SSJ Level of all. First to reach this level was Goku. Vegeta reached it whit one of Bulma's inventions called the Bruto Ray. SSJ 4 has his original haircut (black hair) Has a purple fur everywhere except the cest. You get red eyes and the tail reapeares.