When shopping for electronics pieces, it is vitally important that engineers and electricians know everything they can about a particular piece. After all, if the piece is not of the correct size, or shape, or if it weighs too much, it may not fit properly in whatever device they are designing. And size, shape, and weight are not the only characteristics to consider. Besides these, designers have to worry about the temperatures the device will endure, what solvents it can be exposed to, how much humidity it can take without being damaged, what resistance it might have, how much voltage it can take, and so on and so forth.
To find this information, designers read what are known as