Jak & Daxter. Jak & Dax. Jaxter. Whatever you may want to call it, it's a fun and addicting series. The subtitle of the first game, "The Precursor Legacy", alludes to the Precursors, god-like beings who create the world and the universe around it as well as Precursor orbs which are a kind of rare currency. Kind of.
The series is difficult to tackle because each game seems to exude a different attitude as both the main characters evolve and grow. The first is more innocent with darker undertones as Jak discovers a lot more about Lurkers and time travel than he ever thought he would. While Daxter has to learn how to cope with being turned into an ottsel after falling into a vat of Dark Eco. Eco being a natural gas Jak's village uses as a source of power, with different properties which can be harvested for different uses, like energy or fuel, or say, secret powers.
For the whole of the game Jak doesn't speak and we have to rely on Daxter's witty observations to get a sense of what Jak may be thinking or feeling. Being best friends they are apparently at the stage where they can practically read each other's minds.
Precursor Legacy is more about discovering and unlocking the hidden abilities that Jak has stowed away in his genes and learning more about what kind of world they come from, which comes in handy once you get to the ending and start up the second game (which picks up right where it left off, pretty much).