Trademarks - What is a trademark?

A trademark is a word, phrase, symbol or design, or a combination of words, phrases, symbols or designs, that identifies and distinguishes the source of the goods of one party from those of others.
 
A service mark is the same as a trademark, except that it identifies and distinguishes the source of a service rather than a product. Throughout this booklet, the terms "trademark" and "mark" refer to both trademarks and service marks.

Is registration of my Trademark required?

No. You can establish rights in a mark based on legitimate use of the mark. However, owning a federal trademark registration on the Principal Register provides several advantages, e.g., constructive notice to the public of the registrant's claim of ownership of the mark; a legal presumption of the registrant's ownership of the mark and the registrant's exclusive right to use the mark nationwide on or in connection with the goods and/or services listed in the registration; the ability to bring an action concerning the mark in federal court;  the use of the U.S registration as a basis to obtain registration in foreign countries; and the ability to file the U.S. registration with the U.S. Customs Service to prevent importation of infringing foreign goods.

When can I use the Trademark symbols TM, SM and R..??

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 with the USPTO. However, you may use the federal registration symbol "R" only after the USPTO 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