An article is a type of determiner used before a noun, and it defines whether a noun is specific or not. An article can be broadly divided into an indefinite article ("a" and "an") and a definite article ("the"). A definite article is used to refer to a specific person, place, animal, or thing. For example, in this phrase, "the cup of tea," a specific cup of tea is being referred to. On the other hand, "an" and "a" is used when a statement is general. For example, in this sentence, "Please hand me a book," the speaker is requesting to hand over any random book.