a system whereby a collapsible box may be formed in the same way that standard cardboard boxes are made by folding a single sheet of material is provided . square and rectangular boxes may be constructed which may be collapsed down to compact size and easily popped open . boxes so constructed remain fully assembled with all seams and edges attached even as they are repeatedly folded and unfolded . the box may be made of corrugated cardboard or plastic and easily folded to a fraction of their open volume . the box may open instantly , and when opened , it becomes structural — that is resistant to applied loads — by “ popping ” certain points outwards . an element or construction that is comprised of a sheet of material that has been provided with a network of hinges such that when the element is folded its edges maintain a right angle relationship is also provided .