Clipboard

[1] Another early version of the clipboard, known as the "memorandum file", was invented by American inventor George Henry Hohnsbeen in 1921, for which he was granted U.S. patent 1,398,591.

[1] Clipboards can be constructed from a variety of material, including but not limited to, hardboard, aluminum, PVC, polypropylene, High Impact Polystyrene, and Foamex.

Folding clipboards are usually constructed from a single piece of flexible PVC with two rigid materials enclosed within.

Folding clipboards also provide additional benefits because of the extra space available, allowing the incorporation of pen holders and pockets for storage.

[3] The arrival of the microprocessor and Internet age gave rise to high-tech variants of the traditional clipboard, the first being the Ferranti Market Research Terminal that retained a clip, to hold A4 paper sheets (looking like a large clipboard) but recording answers to questions in its electronic memory.