I am a little confused about the timeline of the Legend of Zelda series. There is a timeline for the series posted on the Legend of Zelda Wikipedia page, which states that the series splits into 3 different timelines after Ocarina of Time. Apparently, Windwaker sits right after OoT, in a timeline where Ganon was defeated and Link is an adult.
However, Ganondorf is in Windwaker as the main antagonist (right?). So, how is he in Windwaker, when he was apparently defeated at the end of OoT?
More generally, I'm a bit confused as to what 'Ganon is defeated/not defeated' means, in the context of the series. I mean, Ganon gets defeated by Link in Link to the Past and in the original LoZ game as well, but then still returns to cause trouble in later installments. Why is his defeat/victory in Ocarina of Time so significant?
(please give a warning if you're going to give significant spoilers!)