Most printers use the same USB cables that other USB devices use to connect to your computer. USB’s development was driven by the need to create a connection standard to replace the myriad serial, parallel, and other cables previously used to connect peripherals to computers. Prior to USB, most printers connected to computers via parallel cables.
Universal Serial Bus development
The Universal Serial Bus is the primary connection type for most computer peripherals. USB was designed to replace the old-school approach that used a different connector type for almost every device that attached to a computer. The USB ports on your computer can be used to attach a keyboard, hard drive, mouse, printer, or any other USB device. USB ports have become so common as the primary means of connecting printers, PC manufacturers have stopped including parallel ports on their machines.
Connectors
Although USB is a standard cable type, there are differences between printer USB cables and other types of USB cables. The end that plugs into the computer will always have the same flat, rectangular connector found on all USB cables. The end that plugs into the printer will have a square connector with curved corners. This is the standard USB configuration, but others exist. Typically, the alternate cable types have smaller ends for connecting to external devices, particularly small, mobile devices.
Purchasing Cables
Any USB cable that has the standard connectors will work with any USB printer. This is important to know because printer manufacturers rarely include a USB cable with the printer itself. The cost of the USB cables varies widely by manufacturer, but the standardized nature of USB means that any cable with the right ends will connect your printer to your computer.
Advantages Over Parallel
Prior to the broad implementation of USB as a printer cable, the parallel cable was the standard for printer connections. In addition to making it easier for people to connect their devices by providing a standardized connection, USB also offers technical advantages over parallel connectors. USB cables can be longer than parallel cables. This allows for flexibility when wiring an office. USB also enables a device to be hot-swappable: you can plug devices in and the computer will automatically make the adjustments required to use the device. Plugging a printer into a parallel port required that the computer be restarted before the device could be used.