Semi-technical history and discussion (all technical terminology linked):

When wireless networking based around the 802.11b standard first hit consumer markets in the late nineties, it looked pretty good on paper. Promising "11 Mbps" compared to original wired Ethernet's 10 Mbps, a reasonable person might have thought 802.11b was actually faster than 10Mbps wired Ethernet connections. It was a while before I was exposed to wireless networking—smartphones weren't a thing yet, and laptops were still hideously expensive, underpowered, and overweight. I was already rocking Fast Ethernet (100 Mbps) wired networks in all my clients' offices and my own house, so the idea of cutting my speed by 90 percent really didn't appeal.

In the early 2000s, things started to change. Laptops got smaller, lighter, and cheaper—and they had Wi-Fi built in right from the factory. Small businesses started eyeballing the "11Mbps" that 802.11b promised and deciding that 10Mbps had been enough for them in their last building, so why not just go wireless in the new one? My first real exposure to Wi-Fi was in dealing with the aftermath of that decision, and it didn't make for a good first impression. Turns out that "11Mbps" was the maximum physical layer bit rate, not a speed at which you could ever expect your actual data to flow from one machine to another. In practice, it wasn't a whole lot better than dial-up Internet—in speed or reliability. In real life, if you had your devices close enough to each other and to the access point, about the best you could reasonably expect was 1 Mbps—about 125 KB/sec. It only got worse from there—if you had ten PCs all trying to access a server, you could cut that 125 KB/sec down to 12.5 KB/sec for each one of them.

Image: D-Link's DI-514 802.11b router. It was a perfectly cromulent router for its time... but those were dark days, friend, dark days indeed.

Just as everybody got used to the idea that 802.11b sucked, 802.11g came along. Promising 54 screaming Mbps, 802.11g was still only half the speed of Fast Ethernet, but five times faster than original Ethernet! Right? Well, no. Just like 802.11b, the advertised speed was really the maximum physical layer data rate, not anything you could ever expect to see on a progress bar. And also like 802.11b, your best case scenario tended to be about a tenth of that—5 Mbps or so—and you'd be splitting that 5 Mbps or so among all the computers on the network, not getting it for each one of them like you would with a switched network.

802.11n was introduced to the consumer public around 2010, promising six hundred Mbps. Wow! Okay, so it's not as fast as the gigabit wired Ethernet that just started getting affordable around the same time, but six times faster than wired Fast Ethernet, right? Once again, a reasonable real-life expectation was around a tenth of that. Maybe. On a good day. To a single device...

In full > https://arstechnica.com/information-technology/2017/03/802-eleventy-what-a-d...