Originally Posted by DamianJ

Proper nouns (also called proper names) are nouns representing unique entities (such as London, Jupiter or Johnny), as distinguished from common nouns which describe a class of entities (such as city, planet or person).[8] Proper nouns are not normally preceded by an article or other limiting modifier (such as any or some), and are used to denote a particular person, place, or thing without regard to any descriptive meaning the word or phrase may have.

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