Functional and descriptive names like Subway and Martha Stewart work when the point is to direct attention to the company brand. They’re not as effective when all they do is explain what the company does. Consider the blandness of these (real) companies: ABC Name Bank, Name Generator, Naming, The Naming Company, Strategic Name Development … and so on and so forth.
Invented names like Oreo, Kleenex and Google are great because they’re memorable and fun to say. Less interesting are names built upon Greek and Latin roots, like Acquient or Agilent. These may be easier to push through the trademark process and come off sounding official, but you better have an advertising budget big enough to explain what it is you actually do.
Experiential names like Infoseek and Magellan play off the experience of using a product or service and make sense to the consumer. But on the flipside, they’re used so often the impact is dulled. For example, Explorer and Safari are browsers–and SUVs.
Evocative names are usually the most successful (Yahoo and Apple), but also the hardest to get right (apparently companies with failed evocative names all disappear).