Glossary

Plain-language electrical and electronics terms.

A quick apprentice-friendly reference for words that show up in calculators, lessons, repair notes, simulator checks, PCB planning, and project guides.

Safety first, always.

ElectroLab AI teaches theory, low-voltage electronics, and planning concepts. Mains voltage, switchboards, fixed wiring, high-current systems, and legal electrical work must only be performed by licensed electricians where required.

Open Safety Center

Term groups

TheoryCoreFaultsBenchPartsAudio/RFAudioMagneticsProtectionSafetyTestingPCB

Theory

AC

Alternating current. Current that changes direction repeatedly.

Theory

DC

Direct current. Current with one main polarity or direction.

Core

Voltage

Electrical pressure or potential difference, measured in volts.

Core

Current

Flow of electric charge, measured in amps.

Core

Resistance

Opposition to current flow, measured in ohms.

Core

Power

Rate of energy use or transfer, measured in watts.

Core

Ground

Reference point in a circuit. It is not always earth.

Faults

Short circuit

Unwanted low-resistance path that can cause high current.

Faults

Open circuit

Broken or incomplete path where current cannot flow.

Bench

Polarity

Positive and negative orientation of a DC part or supply.

Parts

Capacitance

A capacitor's ability to store charge, measured in farads.

Parts

Inductance

A coil's ability to store energy in a magnetic field, measured in henrys.

Audio/RF

Impedance

Opposition to AC that includes resistance and reactance.

Audio/RF

Resonance

Frequency where a circuit or system naturally responds strongly.

Audio

Crossover

Audio filter network that sends frequency bands to suitable speakers.

Magnetics

Transformer

Magnetic device that transfers AC energy between windings.

Protection

Flyback diode

Diode used across a DC coil to clamp switch-off voltage spikes.

Safety

Current limit

Bench supply setting that restricts maximum current during tests.

Testing

Continuity

Meter check that confirms a low-resistance path exists.

Core

Load

The part or circuit using power from a source.

PCB

Decoupling

Using capacitors near ICs to reduce supply noise.

PCB

Footprint

PCB pad layout that must match the physical part.

PCB

Trace

Copper path on a PCB that connects nodes.

Safety

Licensed electrical work

Work controlled by law or regulation that must be done by licensed people where required.