This A–Z glossary defines common electronics, power, display, audio, networking, and storage language in plain English. A general definition does not replace a product specification or model manual.
A–Z index
A · B · C · D · E · F · G · H · I · J · K · L · M · N · O · P · Q · R · S · T · U · V · W · X · Y · Z
A
AC
Current that periodically reverses direction.
Adapter
Device that converts a connector, voltage, or protocol. Related guide.
Ampere
Unit of electric current.
Analog
Signal that varies continuously.
Anode
Electrode where oxidation occurs. Related guide.
Aspect ratio
Ratio of image width to height. Related guide.
B
Bandwidth
Maximum data-carrying capacity of a connection. Related guide.
Battery cycle
Cumulative use equal to 100 percent of battery capacity. Related guide.
BIOS
Firmware that initializes PC hardware. Related guide.
Bit
Smallest binary information unit.
Bluetooth
Short-range wireless communication standard. Related guide.
Boot
Process of initializing hardware and loading software. Related guide.
C
Cache
Fast storage for frequently needed data.
Capacitance
Ability to store electric charge. Related guide.
Capacitor
Component that stores energy in an electric field. Related guide.
Cathode
Electrode where reduction occurs. Related guide.
Codec
Method for encoding and decoding media. Related guide.
Continuity
Unbroken low-resistance electrical path. Related guide.
D
DC
Current that flows in one direction. Related guide.
Dead pixel
Display pixel unable to change correctly. Related guide.
Decibel
Logarithmic unit expressing a level ratio. Related guide.
Device driver
Software connecting an operating system to hardware. Related guide.
DisplayPort
Digital video and audio interface. Related guide.
DNS
System translating domain names to network addresses. Related guide.
E
eARC
Enhanced HDMI audio-return feature. Related guide.
EEPROM
Nonvolatile memory that is electrically rewritable. Related guide.
Electrical ground
Reference potential and safety fault-current path. Related guide.
Electrolyte
Ion-conducting material between battery electrodes. Related guide.
EMI
Electromagnetic interference that disrupts signals. Related guide.
Ethernet
Family of wired local-network standards. Related guide.
F
Farad
Unit of capacitance. Related guide.
Firmware
Stored software controlling device hardware. Related guide.
Flash memory
Nonvolatile electronic storage technology. Related guide.
Frame rate
Number of video frames per second. Related guide.
Frequency
Number of cycles per second.
Fuse
Overcurrent device with a sacrificial element. Related guide.
G
Gain
Increase in a signal's amplitude. Related guide.
Gateway
Device or address connecting different networks. Related guide.
Gigabyte
Decimal unit of one billion bytes. Related guide.
GPU
Processor specialized for graphics and parallel work. Related guide.
Ground loop
Unwanted current path between grounded equipment. Related guide.
GFCI
Device that disconnects power after detecting current imbalance. Related guide.
H
HDD
Magnetic storage drive with spinning platters. Related guide.
HDMI
Digital video, audio, and control interface. Related guide.
Heat sink
Part that transfers component heat to air. Related guide.
Hertz
Unit equal to one cycle per second. Related guide.
Hot pixel
Camera pixel that remains unusually bright. Related guide.
HDR
Media format supporting expanded luminance and color. Related guide.
I
Impedance
Opposition to alternating current. Related guide.
Inductor
Component storing energy in a magnetic field. Related guide.
Input lag
Delay between an input and displayed result. Related guide.
Insulator
Material that strongly resists current. Related guide.
IP address
Numerical address used for network routing. Related guide.
IPS
LCD panel type with broad viewing angles. Related guide.
J
Jitter
Short-term variation in signal timing.
Joule
Unit of energy.
Jumper
Removable link selecting a hardware option. Related guide.
Junction
Boundary or connection between conductive regions.
JPEG
Lossy image-compression format. Related guide.
JST connector
Family of compact wire-to-board connectors.
K
Keystone correction
Projector adjustment that squares a skewed image. Related guide.
Kilobyte
Data unit of 1,000 bytes, or sometimes 1,024.
Kilohertz
One thousand cycles per second. Related guide.
Kilowatt
One thousand watts of power. Related guide.
Kilowatt-hour
Energy equal to one kilowatt used for one hour. Related guide.
Keyframe
Complete reference frame used in video compression.
L
Latency
Delay between a request and result. Related guide.
LCD
Display using liquid crystals to control light. Related guide.
LED
Semiconductor diode that emits light. Related guide.
Lithium-ion battery
Rechargeable high-energy battery chemistry. Related guide.
Local storage
Browser storage kept on a user's device.
Lumen
Unit of total visible light output. Related guide.
M
MAC address
Link-layer identifier for a network interface. Related guide.
Mesh network
Network of coordinated nodes extending coverage. Related guide.
Microphone sensitivity
Output produced for a stated sound input. Related guide.
Motherboard
Main circuit board connecting computer components. Related guide.
Multimeter
Instrument measuring electrical quantities. Related guide.
Megapixel
One million image pixels. Related guide.
N
NAS
File storage available over a network. Related guide.
NAT
Translation between local and public network addresses. Related guide.
Nit
Unit of display luminance. Related guide.
Nonvolatile memory
Memory retaining data without power. Related guide.
NTFS
File system commonly used by Windows. Related guide.
Nyquist frequency
Half a digital system's sampling rate.
O
Ohm
Unit of resistance and impedance. Related guide.
OLED
Display whose pixels emit their own light. Related guide.
Operating system
Software managing hardware and applications.
Optical audio
Digital audio sent as pulses of light. Related guide.
Overclocking
Operating hardware above specified frequency. Related guide.
Overcurrent protection
Device or circuit interrupting excessive current. Related guide.
P
Pairing
Establishing a trusted wireless device relationship. Related guide.
Partition
Defined logical region of a storage device. Related guide.
Pixel
Smallest addressable picture element. Related guide.
Polarity
Positive and negative orientation of DC. Related guide.
POST
Firmware's power-on self-test. Related guide.
Power factor
Ratio of real to apparent AC power. Related guide.
Q
Qi
Standard for compatible inductive charging. Related guide.
QLED
LCD display enhanced with quantum dots. Related guide.
QR code
Two-dimensional barcode encoding data.
Quantization
Mapping values to finite digital levels.
Quantum dot
Nanocrystal converting light to specific colors. Related guide.
Quick Charge
Proprietary family of negotiated charging protocols. Related guide.
R
RAID
Method combining drives for availability or speed. Related guide.
RAM
Fast temporary working memory. Related guide.
Refresh rate
Number of display updates per second. Related guide.
Resistance
Opposition to electric current. Related guide.
Resolution
Pixel dimensions of an image or display. Related guide.
Router
Device forwarding traffic between networks. Related guide.
S
Sample rate
Measurements per second in digital conversion. Related guide.
SD card
Removable flash-memory card family. Related guide.
Short circuit
Unintended low-resistance current path. Related guide.
Signal-to-noise ratio
Desired signal compared with background noise. Related guide.
SSD
Flash-based drive without moving platters. Related guide.
Surge protector
Device limiting specified transient overvoltage. Related guide.
T
Thermal paste
Compound filling gaps between chip and heat sink. Related guide.
Thermal throttling
Automatic performance reduction to limit temperature. Related guide.
Thunderbolt
High-speed data, display, and power interface. Related guide.
Transformer
Magnetic device changing AC voltage or providing isolation. Related guide.
TRS
Tip-ring-sleeve audio connector. Related guide.
Transistor
Semiconductor used to switch or amplify signals.
U
USB
Standards family for data, power, and peripherals. Related guide.
USB-C
Reversible connector supporting several optional capabilities. Related guide.
USB Power Delivery
USB-C standard for negotiated power. Related guide.
UPS
Battery-backed uninterruptible power supply. Related guide.
Upstream
Direction toward a host or network core. Related guide.
UEFI
Modern firmware interface that starts a computer. Related guide.
V
Variable refresh rate
Synchronization of display refresh with frame output. Related guide.
Volt
Unit of electric potential difference. Related guide.
Voltage drop
Voltage reduction along a current-carrying conductor. Related guide.
VPN
Encrypted network tunnel between endpoints. Related guide.
VRAM
Memory dedicated to graphics workloads. Related guide.
VLAN
Logical separation of networks on shared equipment. Related guide.
W
Watt
Unit of power equal to one joule per second. Related guide.
Watt-hour
Energy equal to one watt used for one hour. Related guide.
Wi-Fi
IEEE 802.11 wireless local networking. Related guide.
Write protection
State preventing stored-data changes. Related guide.
WPA3
Modern Wi-Fi security protocol. Related guide.
Waveform
Shape of a signal plotted against time. Related guide.
X
XLR
Locking connector for balanced professional audio. Related guide.
XMP
Memory profile format for RAM settings. Related guide.
x86-64
64-bit PC processor instruction architecture. Related guide.
X-axis
Horizontal coordinate in a graph or sensor.
Xenon flash
Photographic flash using ionized xenon gas. Related guide.
XT connector
Polarized DC connector family used in hobby batteries.
Y
Y-cable
Cable splitting or combining a defined connection.
Yagi antenna
Directional antenna with multiple aligned elements. Related guide.
Yottabyte
Decimal unit of 10 to the 24th bytes.
YPbPr
Analog component-video signal. Related guide.
Yield
Share of manufactured parts meeting specification.
Yoke
Electromagnetic CRT beam-deflection coil.
Z
Zener diode
Diode designed for controlled reverse breakdown. Related guide.
Zero-day
Vulnerability disclosed or exploited before a fix.
Zero-fill
Process of overwriting storage with zeros. Related guide.
Zettabyte
Decimal unit of 10 to the 21st bytes.
ZIF connector
Connector locking a cable with near-zero insertion force. Related guide.
Zone 2
Receiver output serving a second listening area. Related guide.