This document discusses the use of articles (a, an, the) in English. There are two types of articles: definite and indefinite. The definite article "the" is used to refer to specific nouns, while the indefinite articles "a" and "an" are used for general, non-specific nouns. "A" is used before consonants and "an" is used before vowels. Articles are not used with non-countable nouns or when quantities are described. The document provides examples and guidelines for determining article use based on whether the noun is countable, specific or general.