A more thorough explanation:

A notice of allowance is a formal notification from the U.S. Patent and Trademark Office that a patent application or trademark has been approved and can be issued or placed on the Principal Register if it is actually used in commerce.

For patents, the notice of allowance means that the applicant's patent application has been approved and a patent can be issued. However, the patent will not be issued until the applicant has paid the issue fee.

Example: John submitted a patent application for his new invention. After a thorough examination, the U.S. Patent and Trademark Office issued a notice of allowance, indicating that John's patent application has been approved and he can now pay the issue fee to receive his patent.

For trademarks, the notice of allowance means that the trademark may be placed on the Principal Register if it is actually used in commerce.

Example: Sarah submitted a trademark application for her new business logo. After a thorough examination, the U.S. Patent and Trademark Office issued a notice of allowance, indicating that Sarah's trademark may be placed on the Principal Register if she can prove that she is actually using the logo in commerce.

These examples illustrate how a notice of allowance is a formal notification that indicates approval of a patent or trademark application. It is an important step in the process of obtaining a patent or trademark.