Which article is used before plural nouns?

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"). Also, a noun is only used with singular nouns. For example, the sentence, "We get knowledge from a books," is grammatically incorrect. The article 'a' has to be omitted to make it correct.