https://www.techradar.com/news/forget-80211ac-and-meet-wi-fi-5-as-wireless-standards-get-easier-to-understand

Changes are afoot to make the names of Wi-Fi standards like 802.11ac easier to understand by simplifying them to a plain single number.

To that end, 802.11ac – which is used by the majority of contemporary routers – will be renamed just Wi-Fi 5, and the preceding generation 802.11n tech will be called Wi-Fi 4, as you could probably guess. The incoming 802.11ax next-gen Wi-Fi will be – wait for it – yes, Wi-Fi 6.