You see symbols every day in advertisements and on product packaging that represent an important legal tool protecting both consumers and businesses. You recognize the ® and ™ signs, but may not understand their significance.

Both symbols are used to identify a trademark. A trademark can be a word, symbol, slogan, or even a sound, song, or jingle – anything that can be used to identify the source of a particular good or service (while the word “trademark” is used to identify goods and “service mark” to identify services, the term “trademark” is often used to refer to both trademarks and service marks). A trademark’s purpose is to distinguish the goods or services of one person or business from those of another. For example, when you see the famous golden arches (a trademarked symbol), you know you’re visiting a McDonald’s, and not some generic burger joint.

Trademarks thus serve a dual purpose: to assure consumers that what they are purchasing is the product they intend to buy, and to protect the goodwill and investments a company has developed for itself. Customers walking into a restaurant touting the trademarked “McDonald’s” name and logo know that they will be getting food actually sold by the McDonald’s company. On the company’s side, McDonald’s is assured that another company cannot come along, open a restaurant under the “McDonald’s” name, and benefit from the goodwill and reputation that the actual McDonald’s has spent decades developing.

Selecting a logo or name to trademark is important. The degree of protection a trademark provides depends largely on how “strong” the mark is. Simply put, the more unique or “fanciful” a mark, the stronger it is. Arbitrary, “made-up” words (like “Frappuccino,” or “Big Mac”) are particularly strong, whereas common, everyday words (“coffee,” or “hamburger”) are too widely used to qualify for trademark protection. Remember, the point is to identify the unique source of a particular product or service: eating a “Big Mac” is not the same as simply eating a “hamburger.” Common words can serve as strong trademarks when used in a context different from their everyday usage. “Apple” is an obvious example of this. The word would be too generic for use in marketing fruit. But when used to sell computers, it’s a strong mark: the word bears no meaning, in the computer context, relative to its everyday “fruit” usage.

So how do you get trademark rights? There are two routes: register the mark with the U.S. Patent & Trademark Office, or by simply alert the public of your claim to the mark through the use of the ™ or ℠ symbols. A federally registered trademark (denoted by the ® symbol) offers several benefits that the self-claiming route does not, including a legal presumption of ownership of the mark, the ability to bring an action in federal court over use of the mark, the right to use the ® symbol, and the ability to use the registration as a basis for registering the mark in other countries.

Read on for more information on how a trademark might be infringed.