Ratchet & Clank is a platform action game in a similar vein to the 3D versions of the Rayman, Sonic, Mario, or other comparable games. It involves the two protagonists Ratchet, a furry alien creature, and Clank, a nerdy little robot, going on a quest to find Captain Qwark and ultimately to help save the galaxy.
Ratchet & Clank includes many of the common features seen in previous similar games, but distinguishes itself in a number of ways. The game's levels are fairly vast and contain detailed structures which are visible at all times (i.e. there is no distance fog). The game also includes a number of prominently featured mini-games, such as a space fight sequence and a number of turret shoot-outs which are akin to Missile Command in the first person.
The game has over twenty levels (planets) and includes as many cutscenes made with in-game graphics which tell the story. Also of note is that the story is non-linear, requiring the player to return to previous levels to complete objectives and to choose between multiple paths forward. There is also a respectable array of weapons, gadgets, and accessories to find or buy as the game progresses, which offer some unique gameplay features.