https://www.theverge.com/2018/10/3/17926212/wifi-6-version-numbers-announced

If you’ve ever bought a Wi-Fi router, you may have had to sort through specs that read like complete gibberish — like “802.11ac” or “a/b/g/n.” But going forward, Wi-Fi is adopting version numbers so that it’ll be easier to tell whether the router or device you’re buying is on the latest version.

In the past, Wi-Fi versions were identified by a letter or a pair of letters that referred to a wireless standard. The current version is 802.11ac, but before that, we had 802.11n, 802.11g, 802.11a, and 802.11b. It was not comprehensible, so the Wi-Fi Alliance — the group that stewards the implementation of Wi-Fi — is changing it.