This document discusses the use of definite and indefinite articles (a/an and the) in English, as well as cases when no article is used. It provides examples for using definite articles when referring to something unique, specific, previously mentioned, or as a generic term. Indefinite articles are used with singular countable nouns for the first time or when the specific one is unimportant. No article is used with uncountable nouns, plural nouns, abstract nouns, continents, countries, streets, illnesses, and certain expressions involving locations and meals.