This document explains the differences between the articles "a", "an", and "the" in English. The definite article "the" refers to specific or particular nouns, while the indefinite articles "a" and "an" refer to non-specific nouns. The article "an" is used before words beginning with vowel sounds, while "a" is used before consonant sounds. Some exceptions are provided. A quiz with examples tests the reader on proper article usage.