Here is a question a student asked me in one of my A+ certification classes: How can you tell a USB cable version? I honestly don't know the answer and I can't find one either.
USB cables are rated for versions 1, 1.1, 2, and now 3. I have seen their versions on the packaging, but never marked on the cable itself. Since the respective versions are manufactured differently, there is a difference between them.
So, how can you tell?
On Wikipedia: USB cables v.2 and earlier do use a "twisted pair" method, but it doesn't specify if the cables themselves are the same or different. Is the cable rating system for v.2 and earlier just marketing hype?