​There are only two type of articles: difinite articles and indefinite articles.

There are two indefinite articles in English: 'a' and 'an'

The word "a" (which becomes "an" when the next word begins with a vowel - a, e, i, o, u) is called the indefinite article because the noun it goes with is indefinite or general.

Use "a" before a word that starts with a consonant sound ("a bat," "a unicorn"); use "an" before a word that starts with a vowel sound ("an uncle," "an hour").

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The word "the" is known as the definite article and indicates a specific thing. 

​The definite article in English, for both singular and plural nouns, is "the". 

Examples:

The times, the girl, the intelligence, the guide, the musicians.

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The difference between the sentences I sat on a chair and I sat on the chair is that the second sentence refers to a particular, specific chair, not just any chair.

The articles in English are the definite article the and the indefinite articles a and an (and sometimes some).

Use of the definite article implies that the speaker assumes the listener knows the identity of the noun's referent (because it is obvious, because it is common knowledge, or because it was mentioned in the same sentence or an earlier sentence).

Definite article

The only definite article in English is the word the, denoting person(s) or thing(s) already mentioned, under discussion, implied, or otherwise presumed familiar to the listener or reader. The is the most commonly used word in the English language.

"The" can be used with both singular and plural nouns, with nouns of any gender, and with nouns that start with any letter. This is different from many other languages, which have different articles in those situations

example:

The house, the mouse, the vain, the glow, the pray, the grains etc...

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