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Product terms, in plain English

You shouldn’t need a technical dictionary to choose a product. Here’s what the abbreviations, units, and specialist terms in our comparisons mean—and why they matter.

On comparison pages, dotted underlines offer these explanations by touch, mouse, or keyboard. Brand and model names are kept as written.

°C — Degrees Celsius: A temperature scale where water freezes at 0 degrees and boils at 100 degrees at standard pressure.
°F — Degrees Fahrenheit: A temperature scale commonly used in the United States.
2K — A video-resolution label: Used inconsistently in camera marketing. Check the exact pixel dimensions instead of relying on this label alone.
4K — Approximately 4,000 pixels wide: Consumer 4K video is usually 3840 × 2160 pixels. Resolution alone does not determine low-light quality or readable detail.
A — Amperes: Electrical current. Charging power depends on both current and voltage.
AAC — Advanced Audio Coding: An audio format used to send music wirelessly. Your headphones and playback device must both support the format.
AC — Alternating current: Electric current that repeatedly changes direction, as in household wall power. Often used to describe an appliance’s motor type.
ACH — Air changes per hour: How many roomfuls of air a purifier can process in an hour. Compare room coverage at the same air-change rate. Reference for ACH
ADA — American Dental Association: A dental professional organization. Its Seal of Acceptance applies to specific products and claims.
AF — Autofocus: Adjusts the camera lens automatically to keep the subject sharp.
AHAM — Association of Home Appliance Manufacturers: The organization behind the AHAM Verifide program, which verifies air-cleaner performance ratings. Reference for AHAM
AI — Artificial intelligence: Software that recognizes patterns, such as objects seen by a robot’s camera. The label alone does not tell you how reliable it is.
AIVI — Artificial Intelligence and Visual Interpretation: Ecovacs’ name for camera-based object recognition that helps a robot identify obstacles.
ALAC — Apple Lossless Audio Codec: An audio format that preserves the original audio data. Playing a lossless file does not make every wireless connection lossless.
ANC — Active noise cancellation: Uses microphones and opposing sound to reduce background noise, such as engine hum. It does not block every sound.
AOC — Advanced Odor Control: Winix’s name for an odor-control carbon filter. Carbon targets some gases and smells, while particle filters target dust.
aptX — Qualcomm Bluetooth audio format: A family of wireless audio formats. The phone and headphones need to support the same version to use its features.
AQI — Air quality index: A simplified indicator of air quality. A purifier’s display may use its own scale, so check what its colors and numbers represent.
ASIN — Amazon Standard Identification Number: Amazon’s product listing identifier. We use it with model names to avoid counting the same product twice.
AW — Air watts: A measure of vacuum suction power that combines airflow and pressure. It is different from electrical power consumption.
AWD — All-wheel drive: Sends power to all wheels to help maintain traction on slopes or uneven ground.
BPA — Bisphenol A: A chemical used in some plastics and resins. “BPA-free” refers to this chemical, not every possible material in a product.
CADR — Clean air delivery rate: How much cleaned air a purifier delivers over time. A higher number means faster particle removal under the same test conditions. Reference for CADR
CC BY 4.0 — Creative Commons Attribution 4.0: A reuse license that requires giving appropriate credit and noting changes. Follow the linked license for the complete terms.
CFM — Cubic feet per minute: A measure of airflow: how much air moves each minute. Air-purifier clean-air ratings often use this unit.
cm — Centimeters: A unit of length. There are 100 centimeters in a meter.
CMOS — Complementary metal-oxide-semiconductor: A common type of camera image sensor. Sensor size, lens quality, and processing also affect the picture.
CO2 — Carbon dioxide: A gas that can build up in occupied rooms. A particle filter does not remove it; ventilation is a separate consideration.
Codec — Audio or video encoding format: The method used to package sound or video for storage or transmission. Connected devices need compatible formats.
DAC — Digital-to-analog converter: Converts digital audio into the electrical signal used to drive headphones or speakers.
dB — Decibels: A sound-level unit. Lower readings generally mean quieter operation when measured at the same distance and settings.
dBA — A-weighted decibels: A sound-level measurement adjusted to reflect human hearing. Compare readings taken under the same conditions.
DC — Direct current: Electric current that flows in one direction, as from a battery. Some plug-in appliances convert wall power to run a DC motor.
DOL-HDR — Digital overlap high dynamic range: Combines different exposures to help a camera keep detail in bright and dark parts of the same scene.
EDM — Electronic dance music: A broad music category often used when discussing strong bass and energetic sound tuning.
EFLS — Exact Fusion Locating System: Segway Navimow’s name for its positioning system. The sensors and setup differ by mower and version.
EQ — Equalizer: Sound controls that let you adjust bass, middle tones, and treble to your taste.
FAA — Federal Aviation Administration: The United States civil aviation regulator. Battery travel requirements also depend on the airline and route.
FHD — Full high definition: Usually means 1920 × 1080 pixels, also called 1080p.
fl oz — Fluid ounces: A measure of liquid volume. One US fluid ounce is about 30 milliliters.
FOV — Field of view: How wide an area a camera can see. A wider view includes more of the room or road, but makes individual objects look smaller.
fps — Frames per second: How many images a camera records each second. Higher values can make motion look smoother.
ft — Feet: A unit of length. One foot equals 12 inches, or about 30.5 centimeters.
g — Grams: A unit of weight. There are 1,000 grams in a kilogram.
GaN — Gallium nitride: A semiconductor material used in some compact chargers. Check the charger’s actual power rating and ports.
GNSS — Global navigation satellite system: A general name for satellite positioning systems, including GPS.
GPS — Global Positioning System: Uses satellites to estimate location. In a dash cam it can record where you drove; in a mower it helps with navigation.
H × W × D — Height × width × depth: The order of the three measurements: how tall, how wide, and how deep the product is.
HD — High definition: A video-resolution label. Check the actual pixel count and frame rate when comparing cameras.
HDR — High dynamic range: Helps a camera retain detail in both bright and dark areas, such as a face in front of a window.
HEPA — High-efficiency particulate air: A fine-particle filter used to capture airborne dust and other tiny particles. It does not tell you how quickly a purifier cleans a whole room. Reference for HEPA
Hi-Res — High-resolution audio: Audio described as having more digital detail than standard CD audio. The label alone does not guarantee an audible improvement.
HIIT — High-intensity interval training: Exercise that alternates short, intense efforts with recovery periods.
HP — Horsepower: A unit of power. Peak motor claims may differ from sustained operating power.
hr — Hours: A measure of time. Battery runtime depends on settings and usage.
HRTF — Head-related transfer function: Describes how your head and ears change incoming sound. Spatial audio can use it to make headphone sound seem to come from different directions.
HRV — Heart rate variability: Variation in time between heartbeats. It is different from the number of heartbeats per minute.
HVAC — Heating, ventilation, and air conditioning: The equipment that heats, cools, and circulates air through a building.
Hz — Hertz: Cycles per second. In audio, this describes frequency: lower values are bass tones and higher values are treble.
IATA — International Air Transport Association: An airline industry organization. Confirm battery and baggage requirements with your airline before traveling.
IEST — Institute of Environmental Sciences and Technology: An organization that develops technical guidance and test practices. Check the specific test method before comparing ratings from different standards.
in — Inches: A unit of length. One inch equals 2.54 centimeters.
IP — Ingress protection rating: A code for protection against solid objects and water. The first character covers solids, the second water; X means no rating is specified for that part. Reference for IP
IP54 — Dust-protected; splash resistance: Fresh-water laboratory rating. Follow the manufacturer’s exposure limits. Reference for IP54
IP55 — Dust-protected; water-jet resistance: Fresh-water laboratory rating. Follow the manufacturer’s exposure limits. Reference for IP55
IP57 — Dust-protected; temporary immersion resistance: Fresh-water laboratory rating. Follow the manufacturer’s exposure limits. Reference for IP57
IP65 — Dust-tight; water-jet resistance: Fresh-water laboratory rating. Follow the manufacturer’s exposure limits. Reference for IP65
IP66 — Dust-tight; powerful water-jet resistance: Fresh-water laboratory rating. Follow the manufacturer’s exposure limits. Reference for IP66
IP67 — Dust-tight; temporary immersion resistance: Fresh-water laboratory rating. Follow the manufacturer’s exposure limits. Reference for IP67
IP68 — Dust-tight; immersion resistance at manufacturer-specified limits: Fresh-water laboratory rating. Follow the manufacturer’s exposure limits. Reference for IP68
IPS — In-plane switching: A type of screen designed to keep its picture and colors easier to see from different viewing angles.
IPX4 — Dust protection unspecified; splash resistance: Fresh-water laboratory rating. Follow the manufacturer’s exposure limits. Reference for IPX4
IPX5 — Dust protection unspecified; water-jet resistance: Fresh-water laboratory rating. Follow the manufacturer’s exposure limits. Reference for IPX5
IPX6 — Dust protection unspecified; powerful water-jet resistance: Fresh-water laboratory rating. Follow the manufacturer’s exposure limits. Reference for IPX6
IPX7 — Dust protection unspecified; temporary immersion resistance: Fresh-water laboratory rating. Follow the manufacturer’s exposure limits. Reference for IPX7
IPX8 — Dust protection unspecified; immersion resistance at manufacturer-specified limits: Fresh-water laboratory rating. Follow the manufacturer’s exposure limits. Reference for IPX8
IR — Infrared: Light outside the visible range, used by some cameras for night vision or face recognition.
ISO — Camera sensitivity setting: In camera controls, raising ISO brightens the image but can also make it look grainier. The name comes from the International Organization for Standardization.
kg — Kilograms: A unit of weight. One kilogram is about 2.2 pounds.
kHz — Kilohertz: Thousands of cycles per second. Used for sound frequencies and digital audio sampling rates.
kPa — Kilopascals: A pressure unit equal to 1,000 pascals. Common in vacuum suction and pressure-cooker specifications.
L — Liters: A unit of volume used for containers and tanks. One liter is about 1.06 US liquid quarts.
L × W × H — Length × width × height: The order of the three measurements: how long, how wide, and how tall the product is.
lb — Pounds: A unit of weight. One pound is about 0.45 kilograms.
LC3 — Low Complexity Communication Codec: An audio format used by Bluetooth LE Audio. Both devices need compatible support. Reference for LC3
LC3plus — Low Complexity Communication Codec Plus: An audio format related to LC3. Support for LC3 alone does not mean a device also supports LC3plus.
LCD — Liquid-crystal display: A screen that uses liquid crystals to show information, such as battery life or settings.
LDAC — Sony Bluetooth audio format: Can send more audio detail over Bluetooth when both devices support it. Results also depend on the recording, settings, and connection. Reference for LDAC
LDS — Laser distance sensor: Measures distances with laser light so a robot can build a map and plan its route.
LE Audio — Low Energy Audio: Bluetooth audio technology designed for efficient wireless listening. Both devices must support it. Reference for LE Audio
LED — Light-emitting diode: A small, efficient light source used in status indicators, headlights, and display lighting.
LHDC — Low Latency High-Definition Audio Codec: A Bluetooth audio format for compatible phones and headphones. Check support on both devices.
LiDAR — Light detection and ranging: Uses laser light to measure distances, helping a robot map rooms or navigate around objects.
LVP — Luxury vinyl plank: A type of hard flooring made from vinyl planks. Follow the flooring maker’s cleaning instructions.
m² — Square meters: A measure of area. One square meter is about 10.8 square feet.
mAh — Milliamp-hours: A measure of battery charge capacity. Compare at the same battery voltage; the listed capacity is not the amount delivered to your phone.
Mean — Arithmetic average: All the measurements added together, then divided by the number of measurements. Very high or low values can pull it away from the middle.
Median — Middle value: The middle value after the measurements are sorted. Half are at or below it and half at or above it.
min — Minutes: A measure of time. There are 60 minutes in an hour.
mL — Milliliters: A unit of volume. There are 1,000 milliliters in a liter.
mm — Millimeters: A small unit of length. There are 25.4 millimeters in an inch.
ms — Milliseconds: Thousandths of a second. Lower audio-delay figures mean sound follows the action more closely.
Multipoint — Connection to more than one device: Lets headphones stay connected to multiple devices, such as a phone and laptop, so you can switch between them.
NetRTK — Network-assisted precise positioning: Receives satellite-position corrections over a network. Service coverage and subscription requirements depend on the mower.
NO2 — Nitrogen dioxide: A gas associated with combustion. Measuring or filtering gases is different from capturing airborne particles.
OBD — On-board diagnostics: A vehicle’s diagnostic connection. Some dash-cam adapters use this port for power.
OBS — Open Broadcaster Software: An application for recording video and livestreaming, often used with webcams.
OEM — Original equipment manufacturer: The company that made the original equipment. Often used to distinguish its parts from third-party replacements.
OPV — Over-pressure valve: A valve that limits pressure in an espresso machine by allowing excess pressure to escape.
OS — Operating system: The software platform a device runs, such as Windows, macOS, Android, or iOS.
oz — Ounces: A unit used for weight, or as shorthand for fluid ounces on container capacities. Check whether the specification describes weight or volume.
Pa — Pascals: A unit of pressure. Vacuum makers use it for suction pressure, but it does not measure overall cleaning performance.
PC — Personal computer: A desktop or laptop computer. In compatibility lists, this often refers to Windows computers.
PCB — Printed circuit board: The board inside an electronic product that connects its electrical components.
PD — USB Power Delivery: A charging standard that lets compatible devices and chargers agree on power. Charging speed also depends on the cable and device. Reference for PD
PFA — Perfluoroalkoxy polymer: A fluoropolymer used in some coatings. PFA is a particular type of material; PFAS is a much broader chemical group.
PFAS — Per- and polyfluoroalkyl substances: A large group of chemicals used in some coatings and other materials. A PFAS-free claim is broader than a PFOA-free claim.
PFOA — Perfluorooctanoic acid: One chemical in the PFAS family. “PFOA-free” does not mean a coating is free of all PFAS.
PIN — Personal identification number: A short code used to unlock a device or restrict access.
PM1 — Particles up to 1 micrometer: Very small airborne particles. A sensor listing this size measures a different particle group from a PM2.5 sensor.
PM2.5 — Fine particulate matter: Airborne particles no larger than 2.5 micrometers across. This describes particle size, not a purifier’s cleaning speed.
PM10 — Particles up to 10 micrometers: Airborne particles no larger than 10 micrometers across, including some dust and pollen particles.
PPM — Percussions per minute: In massage-gun specifications, the number of pulses delivered in one minute. This measures speed, not how deep or strong each pulse is.
PPS — Programmable Power Supply: A USB charging feature that adjusts power in small steps. Some phones need it for their fastest supported charging.
PSI — Pounds per square inch: A unit of pressure, used here to describe pressure-cooker operating levels.
PTFE — Polytetrafluoroethylene: A fluoropolymer used in some nonstick coatings. Check the manufacturer’s care and temperature instructions.
PTZ — Pan, tilt, and zoom: Camera controls for looking left or right, up or down, and closer in.
QC 3.0 — Qualcomm Quick Charge: A fast-charging system for compatible devices and chargers.
QR — Quick response code: A square code you scan with a phone camera to open a link or start setup.
qt — Quarts: A unit of volume. One US liquid quart is about 0.95 liters.
RGB — Red, green, and blue: The three light colors combined to form colors on a screen or in adjustable lighting.
RPM — Revolutions per minute: How many full turns a motor or rotating part makes in a minute.
RTK — Real-time kinematic positioning: Uses corrections to satellite positioning to help a mower follow a precise route. Performance depends on signal coverage and setup.
RTK-GNSS — Satellite positioning with real-time corrections: Combines satellite navigation with correction data to help a mower follow precise routes. Coverage and setup affect reliability.
SBC — Subband codec: The basic audio format widely supported by Bluetooth headphones and phones.
SCA — Specialty Coffee Association: A coffee industry organization. Its brewer certification evaluates brewing performance against defined criteria.
SD — Secure Digital: A memory-card format used for storing recordings. Check the camera’s required card size, speed, and capacity.
SOS — Emergency distress signal: Here, an emergency-alert feature. Its availability can depend on a connected phone, service, or subscription; SOS is not an acronym.
sq ft — Square feet: A measure of area, such as room size. One square foot is a square one foot on each side.
SSC — Samsung Bluetooth audio codec: Samsung’s wireless audio format. Its available features depend on the Galaxy device and earbuds.
ToF — Time of flight: Measures distance by timing how long a signal takes to return. Robots can use it to judge how far away an obstacle is.
TSA — Transportation Security Administration: The United States agency responsible for airport security screening. Check current travel rules and your airline before packing a battery.
UHD — Ultra high definition: For these consumer cameras, usually means 3840 × 2160 pixels, commonly called 4K.
UL — UL safety certification: A safety-testing and certification mark. Check which product and standard a particular certification covers.
USB — Universal Serial Bus: A connection used for power, data, or both. Check the product’s supported speeds and charging capabilities.
USB-A — USB Type-A connector: The larger rectangular USB connector found on many chargers and computers.
USB-C — USB Type-C connector: The small, reversible connector used for charging and data. Its shape alone does not tell you its charging power or transfer speed.
V — Volts: Electrical voltage. Match the device’s voltage requirements to its power source.
V-FSD — Vision-based Full Self-Driving: Eufy’s name for camera-based mower navigation. It describes the mower’s navigation system, not a guarantee that it never needs help.
VOC — Volatile organic compound: A chemical that can enter the air as a gas, sometimes from cleaners, paint, or furnishings. Particle filtration alone does not remove these gases.
VPM — Vibrations per minute: How many vibrations a device produces in a minute. Counting methods can differ between manufacturers.
W — Watts: Electrical power. For chargers, this helps indicate charging capability; for appliances, it describes power use, not overall performance.
W × D — Width × depth: The two measurements of the space the product occupies on a surface.
W × D × H — Width × depth × height: The order of the three measurements: how wide, how deep, and how tall the product is.
Wh — Watt-hours: A measure of stored battery energy. It accounts for both battery capacity and voltage.
Wi-Fi — Wireless network connection: Connects a device to a local wireless network, often for app control. Supported network bands and internet requirements vary.
XLR — A professional audio connector: A locking connector often used for microphones. It is different from a USB connection.