Trademark
From Wikicpa
A trademark is a word, name, symbol or device which is used in trade with goods to indicate the source of the goods and to distinguish them from the goods of others. A servicemark is the same as a trademark except that it identifies and distinguishes the source of a service rather than a product. The terms "trademark" and "mark" are commonly used to refer to both trademarks and servicemarks.
What Do Trademarks Do?
Trademark rights may be used to prevent others from using a confusingly similar mark, but not to prevent others from making the same goods or from selling the same goods or services under a clearly different mark. Trademarks which are used in interstate or foreign commerce may be registered with the U.S. Patent and Trademark Office, and most trademarks can also be registered in specific states. You do not need to register a trademark in order to hold rights in the mark, however. You can establish rights in a mark based on your legitimate use of the mark in a business or commercial setting.
Using Trademark Symbols
Any time you claim rights in a mark, you may use the "TM" (trademark) or "SM" (service mark) designation to alert the public to your claim, regardless of whether you have filed an application for registration of the mark. However, you may use the federal registration symbol "®" only after the U.S. Patent and Trademark Office actually registers a mark, and not while an application is pending. Also, you may use the registration symbol with the mark only on or in connection with the goods and/or services listed in the federal trademark registration.
From the U.S. Patent and Trademark Office
How Trademarks Differ From Patents and Copyrights
How does copyright differ from trademark protection?
Copyright protects original works of expression, such as novels, fine and graphic arts, music, audio recordings, photography, software, video, cinema, and choreography by preventing people from copying or commercially exploiting them without the copyright owner's permission.
Copyright laws specifically do not protect names, titles or short phrases. That's where trademark law comes in. Trademark protects distinctive words, phrases, logos, symbols, slogans, and any other devices used to identify and distinguish products or services in the marketplace.
There are, however, areas where both trademark and copyright law may be used to protect different aspects of the same product. For example, copyright laws may protect the artistic aspects of a graphic or logo used by a business to identify its goods or services, while trademark may protect the graphic or logo from use by others in a confusing manner in the marketplace. Similarly, trademark laws are often used in conjunction with copyright laws to protect advertising copy. The trademark laws protect the product or service name and any slogans used in the advertising, while the copyright laws protect the additional creative written expression contained in the ad.
What's the difference between patents and trademarks?
Patents allow the creator of certain kinds of inventions that contain new ideas to keep others from making commercial use of those ideas without the creator's permission. For example, Tom invents a new type of hammer that makes it very difficult to miss the nail. Not only can Tom keep others from making, selling or using the precise type of hammer he invented, but he may also be able to apply his patent monopoly rights to prevent people from making commercial use of any similar type of hammer during the time the patent is in effect (20 years from the date the patent application is filed).
Generally, patent and trademark laws do not overlap. When it comes to a product design, however -- say, jewelry or a distinctively shaped musical instrument -- it may be possible to obtain a patent on a design aspect of the device while invoking trademark law to protect the design as a product identifier. For instance, an auto manufacturer might receive a design patent for the stylistic fins that are part of a car's rear fenders. Then, if the fins were intended to be -- and actually are -- used to distinguish the particular model car in the marketplace, trademark law may kick in to protect the appearance of the fins.
From nolo.com
