Frieza is a character from Dragonball Z, a sort of interplanetary real estate broker/dictator/badass. His origins are pretty much unknown, besides the fact that his father, King Cold, at least apparently is of the same race as him. He also has a brother named Coola, who shows up in one of the many DBZ movies, Coola's Revenge.
Frieza has several different forms; by transforming he is able to increase his power dramatically. In all of his forms, he is white and smooth, with some purple coloration (including his lips), and has a tail. In many ways, he seems almost effeminate, which is odd considering he is the most powerful being in the universe (at the time). His initial form (at least, the first one we see him in), he is rather small (almost like a child), with giant horns sticking out of his head. Later, he transforms into a giant, probably about 8 feet tall. When he is attacked by Vegeta, Krillin, Gohan, and Piccolo on Namek, he transforms into his third form, which looks very much like a white, smooth version of the nasties in Aliens. Finally, he gets pissed off enough to transform into his fourth and final form (about damn time!), which is the one he is best known for.
Many years ago (perhaps 10 years before the series Dragonball started), Frieza ruled the Saiyans on Planet Vegeta (among many other planets). They were the foot soldiers in his massive army/business, who were looked down upon by the high class soldiers. Frieza's "business" was pretty evil: his troops would decimate a planet, and then Frieza would sell it to other alien races who wanted to live there. However, Frieza feared one thing: that a Super Saiyan would arise and destroy him. For this reason, Frieza destroyed Planet Vegeta, killing off all but a small handful of Saiyans. Among the survivors were Vegeta, the son of King Vegeta and prince of the Saiyans, who Frieza took in as a student/soldier.
Also among the survivors was Son Goku, who was living on Earth. Coincidentally, Goku left Planet Vegeta the same day that Frieza destroyed it, missing death by at most hours. Bardock, the father of Goku, tried to prevent Frieza's attack, but was killed. As he died, he had a vision that his son would be the one to defeat Frieza.
To make a long story short (this writeup summarizes about 2-3 seasons of DBZ, plus a couple of movies), several members of the Z Fighters ended up on Namek, looking for the Dragonballs with which they would revive the lives of several of their friends. Frieza, through his minions Vegeta and Nappa, had also learned of the Dragonballs, and came to Namek in search of immortality. This eventually leads to several things, including:
- Vegeta rebelling against Frieza and subsequently getting himself killed by Frieza after Vegeta took out several of Frieza's high-level troops.
- Goku showing up and being forced to kick massive ass against a number of nasty foes.
- Krillin and Gohan collecting all of the Namek Dragonballs and bringing Piccolo back to life.
- Powerups for everyone all around, especially Goku, Piccolo, and Frieza.
This eventually ends with the fight of the universe, as Goku faces off against Frieza. Goku manages to hold his own for a while, but only because Frieza is playing around (until the very end, he is only using at most 50% of his full power). Even so, Goku has to use every bit of his strength to keep alive, and his attacks just don't seem to be strong enough to kill (or even seriously injure) his opponent.
Just for fun, Frieza kills Krillin (Goku's best friend), and Goku goes into a rage. In fact, he gets so mad, he becomes a Super Saiyan, a transformation which has not taken place in over a thousand years. This is, all in all, good news for Goku, since he was terribly outclassed by Frieza. Everyone else escapes while the fight rages across Namek. In a desperate move, Frieza fires an enormous ball of energy directly into the core of the planet. Frieza can survive the destruction of a planet, hanging out in space until he can hitch a ride, while Goku... uh... can't.
With about 5 minutes until the destruction of Namek, the fight continues (for about 6 episodes). It's actually quite amazing what the writers do with time dilation; there is actually a half-hour episode which takes up about 5 seconds of time on Namek. It's strange and unrealistic, but it does give a nice impression of how incredibly fast and powerful both fighters are (if the whole episode took 5 seconds, think about how fast each punch is).
Finally, Frieza is defeated. His legs, tail, and one arm are cut clean off, and he has almost no strength left. As Goku prepares to finish him off, Frieza begs for his life, and that big softy Goku actually lets him live. Sheesh. But, as Goku prepares to leave the dying planet, Frieza shoots him in the back with an energy attack. He can't stand the thought of being beaten by a stupid monkey, the weak Saiyans he had always looked down upon. Goku is annoyed by this, and bounces Frieza's attack back into his face. Then Goku escapes Namek just seconds before it explodes.
Fast forward about a year and a half. Goku has been missing in space since the destruction of Namek, but now his friends on Earth have found out that he is about to return. But they sense a powerful energy approaching - Frieza. Yup, he lived. After Namek's destruction, his father, King Cold, found him. Brought aboard the spaceship, he was given robotic parts to replace the limbs he lost, making him (supposedly) even more powerful than before. And, even worse, he will arrive about an hour before Goku does - giving him plenty of time to kill everyone on the planet. Nobody but Goku has the power to fight Frieza, not even the proud Vegeta, who has so far been unable to become a Super Saiyan.
Frieza comes out of his spaceship, looks around, talks for a bit - and is promptly cut into teeny tiny bits, again, this time by Trunks. Trunks is the son of Vegeta and Bulma, and at this time has yet to be born. This Trunks, the young Super Saiyan, has come from the future to give a warning to Goku. But, since Frieza showed up like that, Trunks had to take care of him (Trunks had been trying to keep a low profile, but after easily dispatching both Frieza and King Cold in full view of everyone it got a little difficult to do so).
And that's it for Frieza. Well, actually he shows up in one later episode of Dragonball Z, but it's just for laughs (he breaks out of Hell and then gets creamed by Goku). And, it seems, he shows up in Dragonball GT, but since that series hasn't been released in the US yet I'm not really sure what happens.
Long enough for yah?