A fiber, a single filament of natural material, such as cotton, linen or wool, or artificial material such as nylon, polyester, metal or mineral fiber, or man made natural fibre like Viscose, Modal & Excel is measured in terms of linear mass density, the weight of a given length of fiber.
The vernam cipher, sometimes known as the 'one time pad', is a stream cipher, which providing certain requirements are met, can be theoretically unbreakable.
cipher, cypher(noun) a message written in a secret code. zero, 0, nought, cipher, cypher(noun) a mathematical element that when added to another number yields the same number. nothing, nil, nix, nada, null, aught, cipher, cypher, goose egg, naught, zero, zilch, zip, zippo(noun) a quantity of no importance.