What is the diffirence between Dragon Ball z and Dragon Ball Kai?

Answer 1

They are exacty the same but Kai is remastered and shorter.

Raditz finds Goku, both get killed, Vegeta and Nappa come, Goku comes back, easily beats Nappa, Vegeta lives, go to Namek, Goku beats Freiza, Trunks warns about androids, etc.

Or more specifically:

Earths strongest man (Goku) has been living on Earth and then a spaceship lands on Earth and Goku's brother (Raditz) comes out. He tells Goku that he is his brother and they are from a planet called Planet Vegeta that was blown up by a meteor and Goku is an alien called a saiyan. Goku, Goku's child, Raditz, and two other saiyans called Vegeta and Nappa are the only survivors. Goku always thought he was from Earth but he was sent there from planet Vegeta to destroy it, as all saiyans are evil, but Goku hit his head while a child and the evil went away. Raditz wanted Goku to join him and his evil but Goku said no so Raditz decided to destroy Earth. Raditz was too strong for Goku so he and his old nemesis (Piccolo) teamed up to destroy Raditz but Goku and Raditz ended up dying. On Earth there are 7 magic balls called the dragon balls and when all 7 are joined one can grant any wish. Two other saiyans (Vegeta and Nappa) were sent to avenge Raditz while Earths strongest trained to defeat the and Goku trained in the underworld. When the saiyans arrived Goku was wished back by the Dragon Balls. While he was flying to where the saiyans were all the other Earthlings were being killed. When he made it he easily beat the first saiyan and eventually the other one. but all of his bones were broken. Piccolo created the dragon balls so when he died the dragon balls went too. They went to planet Namek where Piccolo was from to see if there were more dragon balls. Other evil people went too like Vegeta and the strongest known person in the universe (Frieza). With a flick of the finger Freiza killed all of Gokus companions except his son. Goku got so mad he turned into a super saiyan which is where a saiyans hair turns yellow and their power level multiplies by about 50. This had not been done in over 1000 years. Goku easily beat Freiza and returned to Earth where they wished their friends back. A man named Trunks came back from the future to warn them about a new enemy calles the andriod, and that is where it is now.