This document discusses the difference between proper nouns and common nouns. It provides examples of proper nouns like names of people (Ahmad, Mary), places (Kuala Lumpur Twin Towers, London), companies (Ford, Sony), establishments (Maceys, McDonalds), and cultural works (War & Peace, Titanic) which are unique, as opposed to common nouns like boy, woman, country, shop, month, book which can be shared by multiple people or things.