From Jacob Kastrenakes at The Verge:
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.
All of those convoluted codenames are being changed. So instead of the current Wi-Fi being called 802.11ac, it’ll be called Wi-Fi 5 (because it’s the fifth version). It’ll probably make more sense this way, starting with the first version of Wi-Fi, 802.11b:
Wi-Fi 1: 802.11b (1999)
Wi-Fi 2: 802.11a (1999)
Wi-Fi 3: 802.11g (2003)
Wi-Fi 4: 802.11n (2009)
Wi-Fi 5: 802.11ac (2014)
The next version, efficiently dubbed Wi-Fi 6, represents the new 802.11ax standard. For the average consumer, this means very little. I imagine some were able to glean improvement just by the increasing letters (and quantity of letters) but most didn’t care. Now, it’s obvious, version 6 is better than version 5 which is better than version 4, etc.
This new descriptive system is likely to make its way to just about everything that has Wi-Fi capability with the caveat that not all companies will adopt it at the same time. It is a no-brainer and definitely a welcome improvement.