An unseen woman (Alexandra Stewart) relates her friend's reflections of his journeys across the world in such places as Europe, America, Japan and African, including the population who exist in those region's cities, though wildlife played their part as well. But mostly the focus is in Japan.
Sans Soleil (literally, "without sun") is like watching the home movies of one of those people who can't travel anywhere without a camera in their hand, and therefore has turned all the more relevant in the wake of the self-recording phenomenon that enhances/blights the world with its commentaries on the subjects' own lives in a near-constant stream of imagery and information.
If you're looking for a cinematic comparison, it's a bit like Koyaanisqatsi without the enviromental agenda, but with someone talking throughout the film. You may consider this merely to be a pretentious mondo documentary; there is profundity there if you want it (listen for the Pac-Man philosophy), but perhaps, as director Chris Marker's stand-in Stewart playfully imparts, "not understanding adds to the pleasure".
Marker finds some intriguing images, mind you, such as the sex museum, the woman who pretends not to notice the camera, "the Zone", the bloke whomping plastic heads in the games arcade, the giraffe being shot (not for the squeamish), the effects of a volcano, and so on. It had to be pointed out some of this was purely a triumph of editing, as unlike its contemporary Koyaanisqatsi there was a lot of already existing footage being pressed into service rather than original material every few seconds. Even if you didn't wholly grasp the finer points, it carried you along like a cork on a river of sound and vision regardless. Maybe Rubik's Cube dates it; though they're still on sale today, they're a signifier of 1982 like little other pop culture.