Meaning of “folder” - Learner’s Dictionary

folder

noun [ C ] us uk /ˈfəʊldər/
COVER

A2 a piece of plastic or thick paper folded down the middle and used to store loose papers

COMPUTER

B1 a place on a computer where particular files (= documents, pictures, etc) are kept

(Definition of “folder” from the Cambridge Learner’s Dictionary © Cambridge University Press)