There are only three articles: the, a and an. They are very small words which cause very large problems if used incorrectly. If, for example, you wanted someone to hand you the book, but you accidentally said a book, the other person might take some time to go shopping for a book they thought you’d like. While one can never have too many books, work doesn’t get done if we go book shopping every time we need to look up a word in the dictionary. Use of an article can also change the meaning of the noun: