Bel-Air - it means "good air", but really it was named after a tennis player who stuck oil in the 1920's. Now it is home to some of the most exclusive of LA's exclusive canyon gated communities.
Bel Air is generally subdivided into three distinct neighborhoods: East Gate Old Bel Air, West Gate Bel Air, and Upper Bel Air. The largest tracts are mostly closest to Sunset, and the "new money" homes are further up in the Canyons.
What can you say about Beverly Hills that has not already been said? How about this:
Century City isn't really a city at all, rather it's a series of high-rise buildings and a shopping center built on top of the only real bedrock in that part of LA. It was the film lot for 20th-Century & Fox Studios for 50 years previous to being redeveloped in the 1970's.
Malibu is one of the few stretches of Califonria coastline not spoiled by a beachside railway. It was spared because the former owner of Malibu (yes, there was only one at the time) built his own personal railway, which protected his property from incursion under eminent domain via an obscure clause in the federal law governing railway-right-of-way condemnations.
Marina del Rey, like many things in LA, is completely artificial; only the "Mother's Beach" area of the entire marina regularly held water before construction began in 1960, and it was fed by a natural channel from which it is now disconnected.
When Santa Monica was established, it was literally auctioned at the block.
Venice was built by Abbot Kinney, a tobacco magnate, who wanted to re-create Venice, Italy in America.
Most famous since the mid 90's as the former home of OJ Simpson, Brentwood is between Santa Monica and Bel-Air. It's also adjacent to Sawtelle, one of the oldest neighborhoods in LA. While its boundries are vague, it is generally bounded by Santa Monica to the southwest, Pacific Palisades to the west, the Santa Monica Mountains to the north, Bel-Air to the east, and Sawtelle to the southeast.
Culver City was established as a westside city, but boomed when it became an alternative to Burbank and Hollywood as a film and studio /lot location.
Mar Vista sits in the middle of West LA, encamped in all the famous westside "cities".
This elite area above Culver City grew up around the country club from which it took its name.
Known as the home of UCLA, the Westwood area began as a few small developers speculated on a huge, rolling, grassy meadow at the foot of the Santa Monica mountains.