I am building a database of products (and services) and need to put similar items in the same category. That's got to be a common need, and I don't want to recreate the wheel.
For example, a Motorola Razr cell phone would be in a "cell phone" or "mobile phone" category. "Cell Phone" might be in a "communication device" category. Communication device might be in the category called "Consumer Electronics".
Google searches come up with stuff on UPC codes and SKU, yet this way of catogorizing must be used all over the place, such as with AdSense, which must group advertising by topic area.
So, where do I get the lists or standards for product and service categories?