Resistor Grab Bag (pack of 580)

Jargon buster

Plain-language definitions for the technical terms used above.

Axial

Axial components have one lead coming out of each end, so they lie flat or span holes on a circuit board or breadboard. This matters when checking whether the resistor will physically fit your prototyping or through-board assembly method.

PCB

A printed circuit board (PCB) is a board, usually rigid, with etched copper tracks that connect electronic components together without loose wiring. Components are mounted on the board and signals route between them through the copper layout.

ppm

ppm means parts per million, a common way to express very small gas concentrations in air. For CO₂ sensors, the ppm range tells you what levels the sensor can measure, such as normal indoor air through to poorly ventilated spaces.

Tolerance

Tolerance tells you how far the real resistance value may be from the printed value. A 1% resistor is useful when a circuit needs more predictable behaviour than a looser 5% or 10% part.