Articles are words that specify whether a noun is singular or plural and whether it is definite or indefinite.
* Indefinite articles: "a" and "an" refer to any one of a group of things.
* Definite article: "the" refers to a specific thing.
For example:
* a dog (any dog)
* an apple (any apple)
* the dog (a specific dog)
* the apple (a specific apple)