<human>:  When do you use the definite article and when do you use the indefinite article in the Spanish language?
<bot>: The definite article is used with nouns that refer to a specific thing. The indefinite article is used with nouns that refer to a general thing. For example, the definite article is used with the word “el” to refer to the specific thing “the book”, and the indefinite article is used with the word “un” to refer to the general thing “a book”.