- The Universal Serial Bus (USB) is an asynchronous and serial method of transmitting data between devices and has become an industry standard
- Many devices use USB such as keyboards, mice, video cameras, printers, portable media players, mobile phones, disk drives, network adapters, etc
- Different USB connectors exist for different devices. Some examples are:
- USB-A (flash drives, mice, keyboards, external HDD, etc)
- USB-B (printers, scanners, optical drives, floppy drives, etc)
- USB-C
- USB-C is becoming the new standard of USB due to its small size and speed
- When a device is connected to a USB port the computer is:
- Automatically detects that the device has been connected
- Automatically recognised and the appropriate device driver is loaded so that the device can communicate with the computer
- If the device is new, the computer will look for a matching device driver. If one cannot be found then the user must download and install an appropriate driver manually
Advantages and disadvantages of USB
Advantages | Disadvantages |
| Devices are automatically detected and drivers are automatically loaded for communication. This simplifies the data transmission process for the user | The maximum cable length is roughly 5 metres meaning it cannot be used over long distances, limiting its use |
| Cable connectors fit in only one way. This prevents incorrect connections and ensures compatible data transmission | Older versions of USB have limited transmission rates for example USB 2.0 has 480Mbps |
| As USB usage is standardised, there is a lot of support available online and from retailers | Very old USB standards may not be supported in the near future (USB 1.1, USB 2.0, etc) |
| Several different data transmission rates are supported. The newest transmission rate as of 2022 is USB4 2.0 with 80 Gbps (81,920 Mbps, 170x faster than USB 2.0) | |
| Newer USB standards are backwards compatible with older USB standards |
