Tape measures intended for use in tailoring or dressmaking are typically made of flexible cloth or plastic, while those designed for carpentry or construction often use a stiff, curved metallic ribbon that can remain stiff and straight when extended, but retracts into a coil for convenient storage. Surveyors use tape measures in lengths on the order of hectometres. One little-known feature on most tape measures is a small black diamond that appears every 19.2 inches, known as the 'black truss' markings. It is a convenient, common measuring tool. Its flexibility allows for a measure of great length to be easily carried in pocket or toolkit and permits one to measure around curves or corners.
The design on which most modern spring tape measures are built was patented by New Haven, Connecticut resident Alvin J. Fellows on 14 July, 1868. According to the text of his patent, Fellows' tape measure was only an improvement on other versions previously designed. The spring tape measure has been extant since Fellows' patent, but did not come into wide usage until the early 1940s, when it slowly began to supplant the folding wood carpenter's ruler. On Tape-Measures.net there are many more information on measuring tapes and even how to use them.