A
- Access point
- A device that provides a Wi-Fi network for others to join. A home router contains one; extra access points extend coverage. See Router Placement.
- Attenuation
- Loss of signal strength as it travels or passes through materials, measured in decibels. See Building Materials.
B
- Backhaul
- The link that connects access points or mesh nodes to each other and to the router, either by cable or wirelessly.
- Bluetooth SIG
- The Bluetooth Special Interest Group, the organisation that maintains the Bluetooth standard, a short-range 2.4 GHz radio technology.
C
- Channel width
- How much spectrum a Wi-Fi channel occupies: 20, 40, 80, 160 or, with Wi-Fi 7, 320 MHz. Wider channels carry more data but meet more interference.
- Connectivity Standards Alliance (CSA)
- The body, formerly the Zigbee Alliance, that publishes Zigbee and Matter.
- CSIRO
- Australia's national science agency, whose radio astronomy research led to patents used in early Wi-Fi.
D
- dBm
- Decibels relative to one milliwatt, the usual unit for received signal strength. Values closer to zero are stronger.
- DFS
- Dynamic Frequency Selection: a rule for some 5 GHz channels requiring routers to detect radar and vacate the channel.
E
- ETSI
- The European Telecommunications Standards Institute, which writes radio standards used by European regulators.
F
- Faraday cage
- A conductive enclosure that blocks electromagnetic fields, named after Michael Faraday. Foil insulation and metal-coated glass act as partial versions.
- FCC
- The Federal Communications Commission, the US regulator that allocates radio spectrum, including the 6 GHz opening in 2020.
- Fresnel zone
- The ellipse-shaped region around the direct path between two antennas, named after Augustin-Jean Fresnel. Obstacles inside it weaken the link.
H
- Hertz, Heinrich
- German physicist who demonstrated electromagnetic waves in the late 1880s. The unit of frequency carries his name.
I
- IEEE 802.11
- The family of wireless networking standards from the Institute of Electrical and Electronics Engineers on which Wi-Fi is built, first published in 1997.
- ISM band
- Industrial, scientific and medical radio bands usable without a licence, including 2.4 GHz.
L
- Lamarr, Hedy
- Actress and inventor who, with composer George Antheil, patented a frequency-hopping system in 1942, an ancestor of techniques used in Bluetooth.
- Low-E glass
- Energy-efficient glazing with a thin metallic coating that can significantly weaken radio signals.
M
- Marconi, Guglielmo
- Italian inventor and pioneer of practical long-distance radio communication.
- Matter
- A smart-home standard released in 2022 by the Connectivity Standards Alliance, running over Wi-Fi, Thread and Ethernet.
- Mesh network
- Several access points managed as one network, handing devices between nodes as you move.
- MoCA
- Multimedia over Coax Alliance technology that carries network data over coaxial TV cable.
O
- Ofcom
- The UK communications regulator, responsible for spectrum use including Wi-Fi bands.
- OFDMA
- Orthogonal frequency-division multiple access, introduced to Wi-Fi with Wi-Fi 6, letting one transmission serve several devices.
P
- Powerline networking
- Adapters that send network data through household electrical wiring.
R
- RSSI
- Received Signal Strength Indicator, usually shown in dBm by phones and computers.
S
- Spencer, Percy
- Raytheon engineer credited with inventing the microwave oven in the 1940s.
- SSID
- Service Set Identifier, the visible name of a Wi-Fi network.
T
- Thread
- A low-power mesh networking protocol based on IEEE 802.15.4, used by many smart-home devices and by Matter.
W
- Wi-Fi 6E
- Wi-Fi 6 extended to the 6 GHz band.
- Wi-Fi 7
- The generation based on IEEE 802.11be, adding wider channels and multi-link operation.
- Wi-Fi Alliance
- The industry group that certifies Wi-Fi products and introduced generation names in 2018.
Z
- Zigbee
- A low-power 2.4 GHz smart-home protocol based on IEEE 802.15.4. See Interference.