Super Saiyans.

Here are the Super Saiyans shown in the entire Dragon series.

Goku:
Turns super saiyan whilst fighting Freeza.
Turns ultra super saiyan in the hyperbolic time chamber with Gohan.
Turns super saiyan level 2 when training in the after life, but no need to transform to ssj2 until he fights vegeta.
Turns super saiyan level 3 in the Buu saga.
Turns into golden ape in the GT series, Babi saga.
Turns super saiyan level 4 after being the golden ape, with help from Pan.
Turns super saiyan level 5 in the AF series ???

Vegeta:
Turns super saiyan from a shower of meteors, when he was training in a another planet to reach ssj, but simply couldnt do it, with that rage...he did.
Turns super saiyan level 2 when he is being turn into Majin Vegeta.
Turns super saiyan level 3, in the AF series ???
Turns into golden ape in the AF series ???
Turns super saiyan level 4. Bulma used a brute ray. He turns ssj4 before ssj3 and golden ape.

Future Trunks:
Turns super saiyan when Gohan dies (in future)
Turns ultra super saiyan in hyperbolic time chamber.

Gohan:
Turns super saiyan in hyperbolic time chamber with goku.
Turns super saiyan level 2 in the Cell games.

Goten:
Turns super saiyan when training with Gohan, decided to become ssj and does so. The youngest ever to become ssj.

Chibi Trunks:
Turns super saiyan when training with Vegeta.

Brolli:
Turns super saiyan dont know when and how.
Turns ultra super saiyan dont know when and how.
Turns super saiyan level 2 dont know when and how.

Goku Jr:
Turns super saiyan dont know when and how.

Vegeta Jr:
Turns super saiyan dont know when and how.

INSTANT TRANSMISSION