WIRELESS

Wi-Fi

family of wireless networking technologies, based on the IEEE 802.11 family of standards
most commonly uses the 2.4 GHz UHF and 5 GHz SHF ISM radio bands which are subdivided into channels
Wi-Fi's wavebands have relatively high absorption and work best for line-of-sight use
using appropriate hardware, in 2019 speed up to 1 GHz was possible over Wi-Fi
generations:

Wi-Fi 1 (802.11b) - 1 to 11 Mbit/s - 1999 - 2.4 GHz
Wi-Fi 2 (802.11a) - 1.5 to 54 Mbit/s - 1999 - 5 GHz
Wi-Fi 3 (802.11g) - 3–54 Mbit/s - 2003 - 2.4 GHz
Wi-Fi 4 (802.11n) - 72–600 Mbit/s - 2009 - 2.4/5 GHz
Wi-Fi 5 (802.11ac) - 433–6933 Mbit/s - 2014 - 5 GHz
Wi-Fi 6 (802.11ax) - 600–9608 Mbit/s - 2019 - 2.4/5 GHz and 1–6 GHz ISM

different versions use different modulation, 802.11b uses DSSS on a single carrier, whereas 802.11a, Wi-Fi 4, 5 and 6 use multiple carriers on slightly different frequencies within the channel (OFDM)
Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) is the access scheme
modes include infrastructure mode, the most common mode used, where all communications goes through a base station, and ad-hoc and Wi-Fi direct modes
security

WEP - initially Wired Equivalent Privacy (WEP) encryption protected against snooping but it is no longer considered secure since e.g. Aircrack-ng can quickly recover WEP encryption keys
WPA - the Wi-Fi Alliance approved Wi-Fi Protected Access (WPA) which uses TKIP. WPA was specifically designed to work with older equipment usually through a firmware upgrade. WPA2 replaced WPA in 2004. It uses AES. In 2017, a flaw in the WPA2 protocol was discovered, allowing a key replay attack, known as KRACK.
WPS - Wi-Fi Protected Setup was introduced in 2007, but it contained a flaw which let WPA and WPA2 security be bypassed, and effectively broken in many situations. The only remedy as of late 2011 was to turn WPS off. WPS works with a dedicated WPS button, or a WPS PIN (typically printed on the access point). Tools such as Reaver try all PINs as attack.
WPA3 was announced in 2018

Supplicant is the IEEE 802.1X/WPA component used in the client. Implements key negotiation with a WPA Authenticator and it controls the roaming and IEEE 802.11 authentication/association of the wlan driver.
wpa_supplicant - a WPA Supplicant for Linux, BSD, Mac OS X, and Windows with support for WPA and WPA2 (IEEE 802.11i / RSN).
Open1X - free, open source 802.1X/WPA/WPA2/IEEE802.11i implementation - XSupplicant - apparently stalled in 2010.

Also: Bluetooth Low Energy - BLE

US - RAIN RFID.org- RAdio frequency IdentificatioN alliance for use of GS1 UHF Gen2 protocol, i.e. ISO/IEC 18000-63
RFIDchina.org - the IOT (internet of things)