In electronics

Electronics

Electronics is the branch of science, engineering and technology that deals with electrical circuits involving active electrical components such as vacuum tubes, transistors, diodes and integrated circuits, and associated passive interconnection technologies...

, a lead is an electrical connection consisting of a length of wire

Wire

A wire is a single, usually cylindrical, flexible strand or rod of metal. Wires are used to bear mechanical loads and to carry electricity and telecommunications signals. Wire is commonly formed by drawing the metal through a hole in a die or draw plate. Standard sizes are determined by various...

 or soldering pad (smd

Solder mask

Solder mask or solder resist is a lacquer-like layer of polymer that provides a permanent protective coating for the copper traces of a printed circuit board and prevents solder from bridging between conductors, thereby preventing short circuits. Solder mask was created primarily to facilitate...

) that comes from a device. Leads are used for physical support, to transfer power, to probe circuits (see multimeter

Multimeter

A multimeter or a multitester, also known as a VOM , is an electronic measuring instrument that combines several measurement functions in one unit. A typical multimeter may include features such as the ability to measure voltage, current and resistance...

), and to transmit information. The tiny leads coming off through-hole components

Electronic component

An electronic component is a basic electronic element and may be available in a discrete form having two or more electrical terminals . These are intended to be connected together, usually by soldering to a printed circuit board, in order to create an electronic circuit with a particular function...

 are also often called pin

Pin

A pin is a device used for fastening objects or material together.Pin may also refer to:* Award pin, a small piece of metal or plastic with a pin attached given as an award for some achievement...

s.

These pins often either bend under the package body like a letter "J" (J-lead) or come out, down, and form a flat foot for securing to the board (S-lead or gull-lead).