The "r" mark refers to "?", which is the abbreviation of Registered (registered trademark). In the business world, registering a trademark is very important as it protects the independence and uniqueness of a brand. As long as a trademark is registered, the brand is able to use the trademark exclusively and legally prevent other companies from using the trademark to market or sell their products or services internationally.

In the United States, trademarks have some basic rules based on national rules and standards. First, trademarks from different sectors must be unique and not confusing with any other trademarks. Secondly, a trademark cannot deceive or mislead the public. The United States Patent and Trademark Office (USPTO) must conduct a rigorous review before confirming that a trademark is safe and meets standards. Once approved, the trademark holder can register the trademark within 5 years and can use the trademark at will at the end of the trial period.

For those who are considering registering a trademark, it is important to note the following points. First, you need to understand the industry your trademark is in, the competitive threats in the market, and the level of demand. In addition, when designing and forming a trademark, consideration should be given to whether the trademark complies with U.S. legal standards and whether it reflects the company's industry image and brand image. Finally, once you obtain a trademark registration, you should try your best to maintain its validity and avoid losing the protection and rights of the trademark by letting it become invalid or superseded.