Straight from the United States Patent and Trademark Office website:

What is a trademark?

A trademark includes any word, name, symbol, or device, or any combination, used, or intended to be used, in commerce to identify and distinguish the goods of one manufacturer or seller from goods manufactured or sold by others, and to indicate the source of the goods. In short, a trademark is a brand name.


What is a service mark?

A service mark is any word, name, symbol, device, or any combination, used, or intended to be used, in commerce, to identify and distinguish the services of one provider from services provided by others, and to indicate the source of the services.

So ... in summary ... the difference is whether you are providing goods (products) or services. Either way ... filing on the USPTO website is the way to go.

Good luck.