Cumulative files to store and carry other necessities to preserve great works are neat and orderly, lets not lose when we want to document can grab it immediately.
Portfolio piece to store and carry it anywhere easily store documents in order to work on and help documents on where we want the document can not be picked up immediately.
Portfolio pieces can be stored, and can carry convenient collection of documents of various works to be orderly and help documentation is not lost when we need the document can be picked up to use immediately.