GENERAL INFO

Des is an article. It acts as the plural indefinite article ("some" or "any") or as the contraction of the preposition "de" (of/from) and the definite article "les" (the).

USAGE

As a plural indefinite article: "J'ai des amis." (I have some friends.)

As a contraction: "Il revient des États-Unis demain." (He is coming back from the United States tomorrow.)

TRAPS

After negation or expressions of quantity, des usually changes to "de" or "d' ". For example: "Je n'ai pas de questions." (I don't have any questions.) It's often required in French even if omitted in English.