I've done this for Sony Ericsson. Now it's Nokia's turn.

Unlike its major competitor, Nokia uses both letters and numbers to designate most of its models. The use of "E" and "N" are pretty recent, and currently represent the best the Finnish smartphone manufacturer has to offer.

Nokia 1xxx - Ultrabasic series. The simplest of the simple, such as the Nokia 1110i. Don't expect luxuries like 3G and a built-in camera!

Nokia 2xxx - Basic series. Offers a little more functionality than the Ultrabasic, like a special feature marketers incessantly highlight.

Nokia 3xxx - Expression series. Entry-level phones with color displays.

Nokia 5xxx - Active series. For the really on-the-go. The Nokia 5500 Sport is a great example, and I remember my old Nokia 5110 was built like a tank.

Nokia 6xxx - Classic Business series. Actually signifies Nokia's mid-level phones.

Nokia 7xxx - Fashion and Experimental series. Where Nokia usually introduces new features/functionality/designs. Not sure if this still applies today.

Nokia 8xxx - Premium series. Here's where Nokia tries to make a fashion statement, with recent models boasting real stainless steel.

Nokia 9xxx - Smartphone series. Represents Nokia's efforts to create the ultimate business phone. Known for its "Communicator" models, which feature big screens, QWERTY keyboards and generous connectivity options.

Nokia Eseries - Enterprise series. Also for businessmen. The Nokia E61 has already made a name for itself, offering many the 9xxx's capabilities in a more portable package.

Nokia Nseries - Multimedia Computer series. Nokia's kitchen sinks. Mix multimedia and connectivity together. Though I wish some of them were more responsive.

If you really have moolah to burn, check out Vertu. Nokia also tried to figure in the gaming market with the N-Gage and the N-Gage QD. They failed.