A more thorough explanation:

In the field of patents, the term "best mode" refers to the best way that the inventor knows to work the invention described and claimed in a patent or patent application. It is a requirement that a patent application must disclose the best mode known to the inventor at the time of filing. Failure to disclose the best mode can render a patent invalid.

For example, if an inventor has discovered a new way to make a particular product, they must disclose the best mode of making that product in their patent application. If they fail to do so, their patent may be invalidated.

Another example could be a software patent. If an inventor has developed a new algorithm for a particular function, they must disclose the best mode of implementing that algorithm in their patent application.

The best mode requirement ensures that the public is given the most complete and accurate information about the invention, allowing others to build upon it and further advance the field.