Most people know what a standard USB cable looks like, including a 7 year old I know, as well as some some other folks who are well into their 70's.
In other words, the Universal Serial Bus standard is so commonplace that nearly everyone is aware of what "standard" USB connectors looks like, how they plug in, etc.
USB has been so successful that it's now on its third major improvement since first becoming popular in 1998 with USB 1.1. This is fantastic news in the sense that USB is now faster and more ubiquitous, but with those advancements have come more USB connectors and questions about compatibility, speed, and more.
With the release of USB 2.0 in 2000 and then USB 3.0 (called SuperSpeed USB) in 2008 (and very recently USB 3.1), a number of new USB connectors came into existence to enable smaller devices like smartphones the ability to support USB. With each new version also came drastic increases in speed but also then questions about backward compatibility.
One very basic concern is simply what connector physically works with what other connector. For example, does a USB 3.0 Type B plug (the male connector) fit into a USB 2.0 Type B receptacle (the female connector)? (Answer: NO). How about a USB 2.0 Type A plug in a USB 3.0 Type A receptacle? (Answer: YES) See my USB Compatibility Chart if you're curious about any of the other several connectors and their physical compatibilities.
There are lots of other questions too that I'm working on answering in a digestible way, from simple photos of each connector type, to answers about speed and non-physical compatibility.
As I'm putting these resources together, let me ask you: What confuses you about USB? Are there questions you'd like answers to? Diagrams or photos that would helpful? Let me know in the comments!
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