Ganon, also known as Ganondorf, is a character in The Legend of Zelda series who first appeared in The Legend of Zelda, though chronologically speaking he first appeared in The Legend of Zelda: Ocarina of Time. Ganondorf's backstory was first brought up in The Legend of Zelda: A Link to the Past, though his first appearance in a human form was in Ocarina of Time. The A Link to the Past instruction manual gives the character's full name as Ganondorf Dragmire, though the Dragmire surname never appears in the game or any later work. He is generally considered the main antagonist of The Legend of Zelda series, though his contemplated plans are invariably always thwarted by the series hero - Link.
So far, Ganon or his counterpart Ganondorf have appeared in every Zelda game to date, excluding The Legend of Zelda: Majora's Mask, The Minish Cap, Phantom Hourglass, Spirit Tracks, and Skyward Sword.
Ganon has been destroyed and revived multiple times.
Story
Ganondorf was born in Hyrule to the desert people known as the Gerudo. The Gerudo are largly made of women and apparently only give birth to one male a century. And through this sole male in the prominently female tribe are able to give birth to the rest of the offspring although the Gossip Stones of Hyrule suggest that the Gerudo women regularly seek out dates within the town. By Gerudo law the male that is born will become the new king of the Gerudo tribe, even if he happens to be a tyrant. Ganondorf was such a tyrant, and used his influence as king to give him access to the Sacred Realm (referred to as the Golden Land in some games.) Some of his fellow tribe did not follow through his requests. These members were severely punished.
Throughout the series, Ganon's only objective has been to obtain the Triforce and thereby rule the world. As Ganondorf, he was cunning and managed to get his way through to the Sacred Realm by gaining the trust of the Hylian king. The Sacred Realm housed the Triforce, which he touched. Not being balanced in Wisdom, Courage, and Power, however, the Triforce split into three corresponding pieces which went to those chosen by destiny: Ganondorf received the Triforce of Power, Princess Zelda received the Triforce of Wisdom, and Link received the Triforce of Courage. Upon receiving the Triforce of power, Ganondorf was transformed into the evil beast Ganon for the first time, and used his newfound power to overtake the world. Link having been warned of Ganondorf's plans by Zelda, set out to stop him. However, he was too young to wield the blade of evil's bane, the Master Sword, so he had to be sealed away for seven years in the Temple of Time under the protection of Rauru, the sage of light. When Link awoke after the seven years, Hyrule was in ruins. Link, with the help of the seven sages managed to seal Ganondorf away, though his return was inevitable; there would come a day when Ganondorf would return.
It is important to note that Link did in fact return to his original time and prevent most of the events spelled out above from hapening. According to some theories on the Zelda Timeline, this resulted in a split chain of events with two separate resulting timelines: one in which Ganondorf took over the world, and one in which he did not. Also note that Ganondorf, Link, and Zelda still possessed the three Triforce pieces even in the past, for reasons as yet unexplained.
Years later, in the timeline in which Ganondorf did not take over the world, the Sages planned an execution to Ganondorf for his treacherous doings. Upon the time of execution, they were unable to do so, due to his still having the Triforce of Power. Their weapons had some effect, though not enough to kill Ganondorf completely; the sword that was used by the sages only left a glowing scar in Ganondorf's middle. Ganondorf broke free from his chains, began transforming into a the beast, Ganon, and killed one of the Sages, keen on escaping. The Sages, however, had different plans for Ganondorf. Knowing that they were incapable of killing him, they opened the Mirror of Twilight and sealed him in the Twilight Realm. Unable to escape, he deceitfully got the trust of the foolish yet powerful Zant, a member of the Twili who wished more than anything to have the throne of the Twilight Realm. Zant was insane, yet he was willing to do anything that his master told him to, as he viewed Ganondorf as a god.
In the timeline where Ganondorf did take over the world, and was thwarted by Link and sealed in the Sacred Realm, Ganondorf made his reappearance somewhere around four hundred years after the events of "Ocarina of Time" (i.e. Wind Waker). Note that the name Ganondorf is used sparsely in this game, and he is largely called Ganon, even though he never becomes a beast. In this time, the world had been flooded, and what were once Hyrule's mountains had become islands, where the last remaining people lived. Ganondorf set up a base at the Forsaken Fortress, an abandoned pirate hideout. Note that Ganondorf's powers are locked under the sea in the now-ancient Hyrule, and the key to this lock is the Master Sword. In his bid to obtain the full Triforce and rule the world, Ganondorf sent his servant, the Helmaroc King, a gigantic bird, to seek out girls with long ears (i.e. girls with strong Hylian blood), hoping to find the heir to the Hylian throne, Princess Zelda. One such girl was a Pirate leader named Tetra (who in fact was the princess, though she didn't know it). The Helmaroc King caught Tetra somewhere in the vicinity of Outset Island, and the pirates gave chase, shooting at the bird with their cannons. One cannonball hit, and the bird dropped her into the forest on the island. The bird then aimed at the next girl it saw: Aryll, the younger sister of a boy living on the island, who was named Link. Later in the story, this new Link obtained the Master Sword, thus unlocking Ganondorf's powers. When Link confronted him for the first time, Ganondorf easily repelled him, saying that the Master Sword had lost its power (i.e. the power to repel evil). As Ganondorf was about to deal the final blow on Link, Tetra appeared and deterred him. As Ganondorf was about to exact his revenge on her, the Triforce of Power started to glow in the back of his left hand, and thus he discovered that Tetra was, in fact, Princess Zelda. At this time Link and Tetra/Zelda were rescued by a couple of Rito: Quill the Postman and Prince Komali. When Zelda and Link were safely out of reach, the Rito deity, Valoo, appeared and engulfed Ganondorf and his fortress in flames. Ganondorf, being who he is, did not die in the flames. It is assumed that he was at that point able (his powers restored) to return to his fortress, Ganon's Tower, which was underwater along with Hyrule. Eventually, though at what specific time is uncertain, Ganondorf captured Tetra (now a fully-realized Princess Zelda, having been given the second piece to her pendant and thus restoring the Triforce of Wisdom) and took her to the Tower. Link followed later on and confronted him, this time with a fully restored Master Sword and Triforce of Courage (which had been broken and scattered across the Great Sea). Ganondorf brought forth the Triforce Parts from Link and Zelda, adding his own to the mix. The three merged to form the full Triforce, which the King of Hyrule (who had helped Link and Zelda) touched while Ganondorf was gloating. The King was therefore granted one wish, and he wished that Hyrule buried beneath the Great sea and destroyed forever. Ganondorf, realizing that his plans had been ruined, resolved to kill Link and Zelda in his last moments. In the ensuing battle, Ganondorf fought Link with two large swords which resembled the straight sabers used by ninjas. Link kept Ganondorf busy while Zelda shot at him with Light Arrows. In the end, Link finished the battle by impaling Ganondorf's head, turning him to stone. Afterwards, he and the old Hyrule were buried beneath the sea.
It is important to note that, according to the aforementioned timeline theory, Ganondorf/Ganon did return to be the villain in " A link to the Past" (among others), though no game as of yet has documented this return.
Information
The Legend of Zelda
Ganon lusts for the Triforce of Wisdom so that he can go through with his wishes to conquer Hyrule. He is the owner of the Triforce of Power. The game takes place farther ahead than many of the future titles, which explains his appearance as a beast. A Link to the Past revealed that Ganon was not always a beast, but was once human (or more accurately a Gerudo). Due to his inability to get the Triforce of Wisdom, Ganon slowly but surely started to morph into his pig like state as prophesy foretold.
In The Legend of Zelda, Ganon appears as the final boss of the game in Death Mountain. The character will occasionally turn invisible and will also attack in this state. After being defeated the player will have completed the game (though there is a second quest to those willing to play more).
The Adventure of Link
4 years after the events of the original Legend of Zelda game, Ganon's underlings prepare to kill Link while he is on another adventure and use his blood to revive Ganon.
Ocarina of Time
According to Ocarina of Time, Ganon was a member of the Gerudo tribe and was their king, at which time he was named Ganondorf - the sole male of his kind, as only one male is born to the Gerudo every century. Koume and Kotake are described as his surrogate mothers, raising him in an environment where death is an almost-daily event. Ganondorf coveted the Triforce and the lush green lands where Hyrule stood. The hero Link had been used by Ganondorf and unwittingly helped him gain access to the Triforce when Link acquired the Master Sword, unlocking the entrance to the Sacred Realm where the Triforce resided. However, once Ganondorf touched the Triforce itself, it split into its three components that embedded themselves in the three people destined to receive them - Ganondorf received the Triforce of Power, Link the Triforce of Courage, and Princess Zelda the Triforce of Wisdom.
With the Triforce of Power, Ganondorf was able to conquer the land of Hyrule and rule unopposed for seven years, obtaining the title of King of Evil/King of Darkness (Dark Lord or Devil King in the Japanese version). At that point, Link, who had been held in stasis for those seven years, was awakened by Rauru, the Sage of Light. Rauru encouraged him to awaken the other six Sages (whose power had been dormant in the leaders of Hyrule) to oppose and defeat Ganondorf's rule. Now a young adult, Link had succeeded in awakening the Sages and attacked Ganondorf's stronghold for a final showdown. After his initial defeat, Ganondorf's piece of the Triforce, combined with his evil and lust for power, could not contain the evil within his heart. Ganondorf was transformed into an immensely powerful, porcine monster of terrifying evil. After his transformation Ganondorf was to be known as Ganon. After an intense battle, Link and Zelda (whom Ganon needed for the Triforce of Wisdom and Courage) were able to fight and finally subdued the demonic Ganon long enough for the Seven Sages to combine their powers and seal him away. As Ganon screamed that he would return and destroy Link and Zelda's descendants.
Oracle of Ages/Seasons
The Wind Waker
True to his words, Ganondorf broke free from his prison before The Legend of Zelda: The Wind Waker and once again ruled Hyrule with his brutal violence. The people prayed for the Hero of Legend, but the Hero never appeared. There is no clear reason why he did not appear, though one theory states that because he was adventuring in the forsaken land of Termina, he could not defend Hyrule against Ganon. Another states that because the Hero was sent back in time, he did not exist in any form in the timeline of Hyrule's doom. One possible reason for the sages seal to break is that since Link was returned to his child form, time went ahead, to the point where Ganondorf ruled Hyrule before he was defeated by the heroic Link. But this time, Link wasn't there to defeat the Devil King. The people of Hyrule realized that the hero was not going to save them again and began to pray desperately to the gods, Din, Farore, and Nayru. The gods responded by flooding Hyrule with endless rains. Few long-eared Hylians existed. Since cities and towns lay on islands separated by thousands of miles of sea, Ganondorf was not able to control Hyrule very easily. What the King of Evil didn't notice was that on the fishing isle of Outset another hero was being born.
Four Swords Adventure
Four Swords Adventure ganon
In the Legend of Zelda Four Swords Adventure, Ganon is the master mind behind Vaati's escape, Dark Link, and his own plan to take the Triforce. Ganon before the beginning of Four Swords Adventure has stolen the Dark Mirror and used it to procure many Dark Links. This Ganon though is not the same Ganon as from previous game and as you find out from the Gerudos he is a new Ganondorf. He then uses the Dark Links to help Vaati escape and to imprison the maidens and Princess Zelda in 7 different temples. This sends the four Links on a wild goose chase after Vaati and the maidens. During this time Ganon enters the temple within the Forest in which he gains the allegiance of the Dekus. From there he steals the Trident of Power which in the end he uses to turn himself into the beast Ganon as he unfolds his plan after the death of Vaati in the Tower of Wind. He states that he doesn't think that Link can defeat him implying that because Link doesn't have the Master Sword he cannot defeat him. Link, using Light Arrows, incapacitates Ganon in order to imprison him within the Four Sword similarly to how Vaati was at the beginning of this game.
Twilight Princess
In The Legend of Zelda: Twilight Princess, Ganondorf was held on trial for his barbarity, and was evidently chained up, where he was planted by the blade of light. Still, the Triforce of Power managed to keep the murderer alive, where he then ripped right through the chains and killed one of the sages that implanted the sword in him. The rest of the living sages had to resort to opening the Twilight Realm, which sucked him in. In Link's battle with him, he has four phases, one of which sees him possess Princess Zelda.
While in the Twilight Realm, Ganondorf claims to be a god and offers Zant excessive power if he'd manage to set him free from this seemingly dark and gloomy prison that he had been cast into. The power desirous Zant agreed to do this, and with this new gained power - he turned into the king of the Twilight Realm. Some fans believe that Twilight Princess followed an alternate timeline, as Zelda sent Link back to the past in Ocarina of Time, and it is presumed that Ganondorf was captured before he even reached the Sacred Realm, thus explaining why he was set to be executed by the sages.
Spirit Tracks
It is believed that the Demon King Malladus is a reincarnation of Demise's hatred due to his similar apperance to Pig Ganon and Dark Beast Ganon and the fact that is skull form resembles the form Ganon takes when being revived in the Oracle series.
In this game Malladus is revived through Zelda's body but is forced out, he then forces his minion Cole to allow him to take control of his body, altough he transforms into a great beast he is defeated by Link and Zelda.
Skyward Sword
In Skyward Sword, it is revealed that Ganon was originally The Demon King known as Demise, Demise was sealed away and known as the Imprisoned but was defeated by Link. Demise's sword Ghirahim used a ritual that involved Zelda's soul to resurrect his Master.
Although Link defeated Ghirahim, the Ritual was complete and Demise was reveicved, Link and Demise fought a fierce battle but Demise was defeated by Link, due to this Demise cast a curse on link that he would return (as Ganondorf) to destroy him and Zelda in the future.
Super Smash Bros.
Ganondorf appeared in Super Smash Bros. Melee as a secret character. You can unlock him by completing event 29. After that, you have to vs. him and beat him to get him. He has the same moveset as Captain Falcon. In Super Smash Bros. Brawl, he is also a secret character. You can unlock him by either brawling 200 matches OR clearing classic with Zelda or Link on hard OR getting a Zelda and Link trophies in the Subspace Emissary.