Defamation: Speech that is false and damages someone's reputation can be considered defamation and can be subject to legal action.
Obscenity: Speech that is considered "indecent" or "offensive" can be regulated or restricted by the government.
Fighting words: Speech that is likely to incite immediate violence or illegal action can be considered "fighting words" and can be restricted.
Incitement: Speech that encourages or urges people to commit illegal acts can be considered "incitement" and can be restricted.
Child pornography: Speech that involves the sexual exploitation of children is illegal and can be restricted or censored.
Hate speech: Speech that incites hatred or violence against certain groups of people based on race, religion, ethnicity, or other characteristics can be restricted or prohibited.
Espionage: Speech that discloses national security secrets or sensitive information can be restricted or punished as espionage.
It's important to note that the specific restrictions on speech may vary based on the jurisdiction and legal framework of each country.