There are some other differences. Persons can also be used as a Verb: "And Australia, as everybody knows, is entirely peopled with Criminals" You will occasionally hear Person used in adjective form: "He was very personable" (amicable, agreeable). "He was kindness, personified" (if Kindness was a person, it would be him). "I will see to it Personally" (I will attend to this matter without delegating it to another) My own favourite: "I am a people person" - I am a person who likes people :)

Persons is the plural of people (as in "persons unknown"). However in the majority of cases and normal conversation, people will be used instead of persons. Persons is used mostly in official or business language (legal matters and so on).