I don’t know how we got to where we did, but aren’t you glad USB C came along?
In: Technology
Let’s start at the very beginning. USB *actually* started off with just 2 variants: USB-A and USB-B. The idea was that a USB cable would *always* have USB-A on one end, and USB-B on the other. The USB-A side would be the one to say “I’m here!” and send out power. The USB-B side would just wait and do nothing until it got suitable communications from the USB-A side. The nice part of this is that it makes everything really simple. If you’re on the USB-A side, you don’t have to do the work to try and see if anyone is trying to talk to you. If you’re the USB-B side, you don’t have to know how to start conversations. You also don’t have to worry about power coming in when you’re trying to send it out. Back in 1995, keeping it simple like this was good – we will come back to this.
These connectors were made in 1995, for the relatively large machines of the time – thick laptops and desktop computers with plenty of room. So, making them large wasn’t an issue, your peripherals would generally be relatively large too or have the cable built in.
Then, devices started getting smaller. They introduced a new, smaller connector, “mini USB”. They made a mini version of USB A and USB B. The wires were the same, just the plug was smaller. This wasn’t small enough for a lot of uses, so they wanted to make it even smaller – and they did, introducing micro USB, which was even *smaller* and had micro A and micro B
Then, they wanted to make an even faster version of USB… But the wires they had just couldn’t take it. The first versions of USB had just four wires, and only two of them carried data, not great. So they needed to add more wires… But most of the connectors were just too small! They had made all those mini and micro versions too small to add more wires, so they had to make the connector bigger in some way (but ensure you could put an old plug in a new socket). They didn’t bother making new versions with extra wires for mini USB A, mini USB B or micro USB A, because they weren’t used that much – but the shape of the new version of standard USB B and micro USB B was different to the old one.
Now, we come to around 2014. This whole situation kinda sucks, and you can’t make USB “universal” the way device manufacturers want to – it’s inherently really hard to use the same port to charge a device *and* send data out to a connected device, all the solutions kinda suck. At the same time, those concerns we had 20 years ago about “but it’s so hard to have everything listen and know how to start communications” aren’t as major, because of how much more computational power everything has. So, they decide to make *one* connector that can *actually* do it all – it can start the conversation, it can just reply, it can send out power or it can receive it. They couldn’t make it back then because computers weren’t as powerful, but they can now!
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