A more thorough explanation:

Fighting words are words that are intended to provoke violence and may not be protected under the First Amendment of the United States Constitution. The Supreme Court defined fighting words in the case of Chaplinsky v New Hampshire (1942) as words that "by their very utterance, inflict injury or tend to incite an immediate breach of the peace."

Examples of fighting words include racial slurs, insults, and threats of violence. For instance, if someone were to use a racial slur against another person with the intention of provoking a physical altercation, those words could be considered fighting words.

However, not all offensive speech is considered fighting words. In the case of Texas v. Johnson (1989), the Supreme Court ruled that burning the American flag, while offensive to some, was not considered fighting words because it did not directly provoke violence.

It is important to note that even if speech is considered fighting words, it may still be protected under the First Amendment if the restriction on speech is based on viewpoint discrimination. This means that the government cannot punish speech simply because they disagree with the ideas expressed.