Electromagnetic wave based communications have been utilized for many decades

• 1. Radio and Television
• 2. Voice conversation (Cellphones)
• 3. Militaries

Early wireless quipment was expensive proprietary and not interoperable between vendors as it used unique and non standard modulation methods.

• 1880 - Photophone - Used between buildings in Washington DC - Alexander Graham Bell - Light was used.
• 1901 - Guglielmo Marconi transmitted and received the first transatlantic wireless Morse code signal—the letter “S” (three dots: ···)
• 1927 - First telephone service between NY and London
• 1924 - Bell Labs had created a two way voice carrying radio wave.
• 1940 - Voice technology was widely used.

Industry Organizations

• Regulations - FCC
• Standardization - IEEE
• Comptability - WiFi Alliance

Standard	Year	Band
802.11a	1999	5 GHz
802.11b	1999	2.4 GHz
802.11g	2003	2.4 GHz
802.11n	2009	2.4/5 GHz
802.11ac	2013	5 GHz
802.11ax	2019	2.4/5/6 GHz

Amendment	Common name	Notes
802.11n	Wi-Fi 4	MIMO
802.11ac	Wi-Fi 5	5 GHz focus
802.11ax	Wi-Fi 6/6E	OFDMA, 6 GHz