A USB (short for Universal Serial Bus) port is a standardised connection used in computers and consumer electronic devices for short-distance digital communication. They allow the devices connected to one another to transfer data between each other; they also supply electricity to charge the devices or to run them.
There are wired and wireless versions, but only the wired versions use ports and cables.
Which devices can use a USB port?
Many electronic devices use USB interfaces, usually for computer networking:
- USB network adapters;
- USB printers on home networks;
- USB modems (broadband and cellular), and
- If there’s no network, USB drives can transfer files between computers.
How to use a USB port
You can connect two devices with a USB cable by plugging each end into a port. It doesn’t matter whether the devices are on or off, but take care when unplugging a USB cable when a device is running as this can cause damage.
You can connect several USB devices to each other with a USB hub. A hub connects to one USB port and has additional ports for other devices to connect to it. Use a separate cable for each device and plug them individually into the hub.
USB-A, USB-B and USB-C ports
USB-A ports aren’t very common. They’re almost square in shape and are often used for mice and keyboards.
USB-B ports are more common and are rectangular in shape. They’re found on printers, computers, games consoles and routers, as well as USB sticks.
USB-C ports are smaller than A and B and have been designed to replace both these older types as devices become slimmer and smaller.
Micro-USB ports are the smaller versions of A and B and they’re used a lot on mobile devices.
You can connect devices that have two different port types by using the right sort of cable to fit both ends. USB cables have been designed and manufactured with this in mind, so it’s not usually a problem.