I found an interesting article on climate change in today's newspaper.

The definite article is used to indicate a specific object.

I bought a book yesterday.

The zero article is not used in this sentence.

I read an interesting news article this morning.

This article of faith is fundamental to our belief.

The articles in this newspaper are very interesting.

Definite articles are important for French grammar.

Indefinite articles are important for French grammar.

Zero articles are often used in this type of document.