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This glossary is a quick reference of most of the terms used in this website. The definitions have been simplified. In some cases the simple definition given may not be 100% accurate but has been kept simple for the purposes of this website. Click on the words that are blue & underlined to be taken to Wikipedia for more information.    Note:  Wikipedia should be considered as a starting point and not as an authorative source.

AC (Alternating Current Electricity) - Electricity where the current alternates in direction. The type of electricity found in the wall plug of your home.

Amp (Ampere) - A measurement of electrical current.

Breadboard (or solderless breadboard) - a reusable solderless device generally used for prototyping and experimenting with circuits. See:

Cam - A projecting part of a wheel used to create a reciprocating motion in a lever (called a follower) that makes contact with the cam.

Capacitor - An electronic device for storing an electrical charge.

Circuit - An unbroken path through which energy can flow without beginning or end.

Current (electrical) - A flow of electrical charge.

DC (Direct Current) Electricity - Electricity where the electrons flow in one direction (from negative to positive.) The type of electricity produced by common household batteries (AA, C, D).

Gauge (electrical wire) - Gauge is a measurement of electrical wire diameter. Increasing gauge number indicate decreasing wire diameters.

Gauge (sheet metal) - Measurement of the thickness of a piece of sheet metal. Increasing gauge numbers indicate decreasing metal thickness.

OHM - A unit of measurement of electrical resistance. The higher the number the more resistance to the flow of electricity.

PERF Board - A perforated circuit board using for building electrical circuits. A perf board may have a copper pattern printed on the board to facilitate soldering of components.  See:

PIC (Programmable Integrated Circuit) - A computer on a chip with a processor, memory to hold and run a program and input and output pins.

Potentiometer - A variable resistor.

PSI (Pounds per Square Inch) - Unit of measurement of pressure (or force) in liquids and gases.

Pulse Width Modulation - Refers to controlling an electrical signal by modulating (or changing) the duty cycle. Used either to send information (when used to control a Servo) or to control the amount of power sent to a load (when used to control the speed of a motor).

Relay - An electrical switch that opens and closes under the control of another electrical circuit.

Resistance (electricity) - A measurement of the degree to which an object opposes the flow of electrical current

Resistor - An electrical component that restricts (or resists) the flow of electrical current. - Revolutions Per Minute - A measure of the number of full rotations a device makes in one minute.

Servo (RC) - A dc motor with a position feedback mechanism that can be controlled to move to any position using pulse width modulation.

Stepper Motor - A brushless motor that divides a full rotation into a large number of steps. When controlled electronically, a stepper motors position can be precisely controlled.

Switch (electrical) - A mechanical device used to connect and disconnect a circuit.

Torque - A measure of how much a force acting on an object causes that object to rotate.

Volt - A measurement of electrical pressure.

Voltage - A quantitative expression of the potential difference in charge between two points in an electrical field.

Voltage Ohm Meter (Multimeter) - An instrument used in electronics to measure voltage, amps and ohms. Some multimeters have the capability of checking other components (not currently mentioned on this website.)

Watt (electricity) - A unit of measurement of power. In electricity it is defined as Voltage times Amps.