Frieza (or Freeza depending on how you prefer to spell it and what version of Dragon Ball you watch) is one of the main villains in the Dragon Ball series and is many people's favorite villain, and reaches the top of many top villain lists. He is threatening, destructive, unforgiving, and egotistical, and sees to take out anyone that disobeys him or he sees as useless. He is a favorite character to many, and is considered one of the best villains in the entire series by many fans. This page will be dedicated to information about him and what he did in the Dragon Ball series.
At the start of the series, Frieza was the complete emperor of the universe, and he controlled his own complete army and was feared for his ruthlessness and power. He was the son of King Cold, and his actions led to Goku arriving on Earth. He ruled over many planets, including the Saiyan's home planet, Planet Vegeta, and commanded his army, known as the Frieza Force, to control them. In Resurrection of F, it was stated that he controls at least 448 planets. From these planets he gathers soldiers, and 
eventually he gathered a group of elite soldiers called the Ginyu Force. His most used soldiers were the Saiyans, who were powerful enough to take a planet even in just a small group. He heard legends about a Super Saiyan, but brushed it off as just a myth until a rising group of incredibly strong Saiyans started to raise his concern. Recently there has been rising evidence that Frieza had befriended the God of Destruction Beerus, and Beerus had asked Frieza to destroy Planet Vegeta, and Frieza did not do it because of the Saiyans themselves. After destroying Planet Vegeta, he continued his rule with the few surviving Saiyans, Nappa Vegeta and Raditz, in his army. Because of destroying Planet Vegeta, he spiraled off the entire series as we know it, and eventually that came back to destroy him.
We do not know much about Frieza's past or childhood, but we know enough to put together a story. It has been stated that Frieza is a mutant in his species due to his father being one as well. Because of this mutation, him and his father are the only members of the Frieza Race who possess such a high level of power and brutality. However, even compared to his father, Frieza's mutation is much stronger, making him a complete prodigy and the strongest of the Frieza Race. Because of this he has never needed to train a day in his life, and his immense power is just natural. It has also been alluded to that Frieza used to fight with his parents, and he hasn't had to dust himself off after a battle since then. There is a large gap in what we know after that, and at some point after growing up Frieza formed his army and began conquering planets like his father did. At some point, Frieza's father told him that there are only two beings in the universe that he should never cross, Majin Buu and Beerus. But at some point Frieza met Beerus, and they got along quite well due to their shared interest in destroying things. However, Frieza got carried away and angered Beerus, causing them to fight, with 
Beerus easily winning. Beerus demanded that Frieza destroy Planet Vegeta, as he didn't want to do it himself. After that Frieza encountered the Galactic Patrol, and he easily defeated them, so they determined that they needed to stay away from him at all costs. Eventually he realized that the Saiyans were becoming more powerful, and some were beginning to rebel. Because of this and his previous encounter with Beerus, he decided to destroy Planet Vegeta and almost completely wipe out the Saiyans, keeping the remaining ones in check in his army. He used his army to take over planets, take members of their race for his army, and possibly sell the planet for profit. However, eventually he heard of something that could keep his reign over the universe eternal, the Dragon Balls. He went to Namek to find them, sending troops and staying back to watch them take the balls, but Krillin, Gohan, and eventually Vegeta began to interfere. This led to a major loss of his army including the Ginyu Force, and eventually the Dragon Balls were lost and he became enraged. His chance at immortality was gone, so he attacked the group that had been interfering. He killed Krillin and Vegeta and fought with Goku, which led to Goku going Super Saiyan and the battle completely destroying the planet Namek. He seemed defeated, but he was still alive, severely damaged and floating with the remains of Namek until his father found him and repaired his body with robotic parts. He then returned to Earth, where he wanted to get revenge on Goku, but ended up getting killed by 
Trunks along with his father. But, despite their deaths, Frieza's army continued to function, under the new management of Sorbet and Tagoma. The army was doing poorly, and Sorbet proposed that they use the Earth's Dragon Balls to revive Frieza so he can lead the army once more. They collected the Dragon Balls and Frieza was revived, and he took control of the army. He insisted he get revenge on Goku and Trunks, and trained himself for four months. He then went to attack Earth, using his army against the Z-Fighters until Goku and Vegeta show up. He then transforms, battles Goku, and reveals he can transform further, and goes into his golden form. He fights Goku, and wounds him, and Vegeta steps in, and eventually Frieza destroys the entire Earth along with himself out of rage of being defeated. Whis rewinds time, and Goku stops Frieza from doing this, defeating him once more and saving Earth.
Frieza is a sadistic villain who loves to see death, agony, and destruction, and loves to toy with his enemies and make them suffer. He has been shown expressing immense joy when destroying planets, describing the explosions as "fireworks" and laughing at the carnage. He has a huge amount of power to go with his sadistic personality, and because of this, he has displayed a large ego. He also is very clever when toying with his enemies and will often crack jokes, as when he was fighting Vegeta, he stated that there are only three things that he can't tolerate, cowardice, bad haircuts, and millitary insurrection, and he tell Vegeta that he posses all three of those traits. He possesses a dark sense of humor, and is aware of his reputation for brutality, and doesn't deny it at all. He is usually seen having a calm mood, and is 
only driven over the edge after constant annoyances or when losing a fight. Frieza is extremely confident in himself and his abilities, and will typically show them off by not using his hands in a fight or other ways to show his prowess in a fight. His view of being superior to any opponent is shown in both his dialogue and music about him, as he commonly refers to his opponents as ants or worms, and refers to himself as a dinosaur. Despite this, he can be pushed to the point of making rash judgements and decisions, which was shown when he destroyed Planet Vegeta. To add to his arrogance, he is very narcissistic and will violently react to those who criticize him or his power. This makes him similar to other villains in the series, but what differs him from them is that he is mostly shown being very calm and refined. He will use very polite and regal language when talking, while other villains use a more rash and strong way of speaking. But, despite this regal outside, he is still cold-hearted, and his ruthless traits still show, along with his intellect. However, despite being smart, he will get cocky, which will cloud his judgement and cause him to become overzealous and underestimate foes, which led to his ultimate defeat several times. After his defeat on Namek he became obsessed with killing Goku and his friends, which was shown both after becoming Mecha Frieza, when he headed straight to Earth, and after being revived as he refused to let go of his grudge. Along with his hate for Goku's power, he has revealed that he finds Goku's kind personality sickening to the point of physically wanting to vomit, which shows off his complete evil personality even more. Frieza is even ruthless towards his minions, and doesn't seem to care for their wellbeing at all, to the point of even murdering them without a care on multiple occasions. He has even been shown killing his minions just because they showed fear or even a slight sign of remorse.
Frieza is one of the many characters in Dragon Ball that can transform, but he does not transform to increase power, as his other forms are only there to conceal and control his already immense power. As of now Frieza has five cannon transformations, three of which were made to conceal his power, and his fourth form being his true form. It has been stated that Frieza struggles to control even his second form, and needs immense focus and stamina in order to use them. After his training he was able to transform 
straight from his first form to his final form, along with adding the fifth golden form. He enjoys using his weaker forms however, as it gives his enemies a false sense of hope that they can beat him.
Frieza's first form is small and simple, and appears more humanoid than the others. He has what appears to be a chestnut shaped helmet of some kind attached to his skull, which is white with a purple orb in the center. From this attachment comes two straight black horns that protrude at near 45 degree angles. He has a tail with a sharp purple end that is rather thick in width and able to crack the ground when slammed. He has three talon-like toes as feet, with black nails at the end of them, similar to toenails. He has small purple sections on his shoulders and abdomen when not wearing armor, and his legs, arms, cheeks and the base of his tail are pink with thin black lines. His hands, feet, face, and neck have a lilac color, and the majority of his arms and legs are covered by thick white wrist and ankle bands that have brown sections on the front. He has red pupils and his lips are colored with a dark purple, and he wears the upper body armor seen being worn by his army with purple coloring on the chest plates, and is occasionally seen wearing a pink colored scouter. His power level in this form has been stated to be 530,000.
Frieza's second form is similar to the first, and still human-like, but is much larger in height and muscle mass, and appears more mature while his first form seems child-like. His horns become larger and sharply curve upwards at near right angles instead of just protruding straight out. His armor no longer fits, and completely shatters when he transforms, and his natural white colored bio-armor covers his chest and shoulders instead, similar looking to the armor that sits underneath his previous armor in his fist form. The armor displays purple sections on the top of his shoulders and in the center of his abdomen. His arm and ankle pads from his first form remain, but cover less skin, and his power level increases.
Frieza's third form looks more brutish and much less humanoid, and his skull has elongated. His facial features change, leaving him with no visible nose and his mouth forming a shape similar to a beak. His horns disappear and are replaced
with white horns that are a part of his skull, protruding in pairs along it. Two white spikes similar to the new horns protrude from his back and curve slightly, long enough to be visible from the front of his body. The armor on his shoulders is no longer flat, and sticks out to look like a pair of shoulder pads, and the purple sections grow along with it. He walks and stands with a slight hunch in his back, as if his body cannot support itself due to its weight. When this form is seen Frieza's tail is cut slightly due to a fight when he was in his second form, but we can assume that the tail would have an end to it if it had not been cut. Frieza has stated that no one had ever seen his third form before, and the exact power level of the form is unknown, but it is slightly stronger than his second form.
Frieza's fourth and final form is the form that Frieza was born in, and differs greatly from the last three. His bio-armor is seen cracking and shattering, revealing just his skin, making the form look short and sleek. The form seems to look like a combination between a lizard and a human, and looks more calm and less brutish than previous forms. His horns and spikes have disappeared, and his physique becomes streamlined. His skin changes from a light lilac to a pure white color, with the helmet looking part on his 
skull disappearing, put the purple section on his head being left there, along with the purple section on his shoulders, forearms, abdomen, and shins. The pink sections on his cheeks are gone, but there are two black lines going from the bottom of his eyes to his chin that remain. His pupils are still red, and his lips are still the same color, and all injuries he took in previous forms have been healed. His arms and shins still don the wrist and ankle bands, but they are the same white color as the rest of his skin and almost seem to blend in. This form allows Frieza to reach his full potential and according to him, the only people who have been able to harm him in this form are his father and Goku. There is another variation of this form, which is used when Frieza is at 100% power. His muscle mass increases immensely, causing a large strain on his body. He cannot use this form for too long, as he will slowly weaken due to the amount of power he is using and the fact that his mass is hurting his stamina.
Frieza has another form that he achieved later on, a fifth form known as "Golden Frieza" because of its 
shining gold color. The basic appearance of this form is similar to his true form, but certain things are changed. The skin on his face, hands, and feet becomes a dark purple, and the rest of his skin is encased in a shining gold colored bio-armor that becomes a darker gold on his arms and legs. The purple sections on his shoulders are gone and the ones on his arms and legs become more oval shaped. He also becomes slightly taller and gains a little more muscle mass, and his aura changes to a fiery orange color.