A trademark may be practically any word, phrase, symbol, design, logo, or other unique indicator of origin that is used in association with the sale of goods or services.
The first U.S. trademark registration for the iconic game by the Bob's Space Racers company. REGISTERED TRADEMARK 2,561,937
A "famous mark" - one that is widely recognized by the general public as a destination of the source of the goods or services of the mark's owner - is subject to a high level of protection under special federal statutes.
Prior to formal registration with the United States Patent & Trademark Office (USPTO), a trademark should be identified in at least the first instance of its use in every article of literature where it is used, by placing the superscript or subscript "TM" after the trademark.
A service mark has the same legal significance as a trademark except that a service mark is used in association with the sale of services. Prior to formal registration with the USPTO, a service mark should be identified in at least the first instance of its use in every article of literature where it is used, by placing the superscript or subscript "SM" after the service mark.
A registered mark is a mark that has been filed with the USPTO and which has received an official certificate of registration. All registered marks should have the symbol ® adjacent to the mark whenever it is used in any setting, at least in the first instance of use in that setting.