Articles are the words that are used with a noun to indicate the type of reference being made by the noun.
In English language there are two articles: the and a/ an. ‘The’ is used to refer to specific or particular nouns – definite article; ‘a/an’ is used to modify non-specific or non-particular nouns – indefinite article. Use of an article can also change the meaning of a noun, so traditionally, an article is usually considered to be a type of adjective in English. As articles are used very often, these are important for us to learn.
Many nouns, especially singular forms of countable nouns must have an article. In English, it is not possible to say a sentence as ‘I sat on chair’ without an article, but a demonstrative or possessive adjective can be used instead of an article as in the sentences ‘I sat on that chair’ and ‘I sat on his chair’.
Whenever you see an article, you will find a noun with it. The noun may be the next word as in ‘the book’ or there may be adjectives and perhaps adverbs between the article and the noun as in ‘the extremely lengthy book.’
Articles in English are complicated, and there are many rules for their use. There are some common types of nouns that don’t take an article, such as, names of sports: hockey, baseball, etc.; names of academic subjects: history, chemistry, etc.