First let me know “What is a USB cable?”
As what I mentioned, you may notice that it’s necessary to prepare a charger and a USB cable before charging a power bank 10400mAh. Read this article if you don’t know a lot about portable charger, here I will give a brief introduce about the USB charging cable/micro USB cable.
USB stands for Universal Serial Bus, it always means a digital data communication, which you can regard it as a data short-term travel from one device to another. Here, you should also know about the USB connector, a standard cable connection interface for personal computers and consumer electronics devices. So, what is USB cable? USB cables are long or short cables with USB ports to connect computers to peripheral devices.
Why most of USB cables are black and white?—Have you ever found that although USB cables colors are various, but most of the USB cables are black and white. Why?
Apple is a pioneer who use the white earphone/USB cables at the first. It says that they decided to make the earbuds & earbud cables recognizable. The early iPod ads all showed silhouetted people with bright white earbuds & earbud cables. And as a result, whenever you saw someone on the street with white earbuds/cables, you knew they were using an iPod — even though the actual device was in their pocket/bag, and even if they were, say, wearing a hoodie that hid the actual earbuds. To keep the Apple accessories stay the the same, they decide to produce white USB cable at the same time. With the big influence of iPhone, some competitors begin with white USB cables, too.
About the black USB cable, because most electronic devices are designed with black cables and it works as a convention which followed by most manufacturers. To be frankly, most of cables are black and I think what’s most relevant is that the black is always stand for classic and solid.