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USB Port Overview: Differences between USB-A, USB-B & USB-C

Updated on Thursday, May 16, 2024

iBoysoft author Connie Yang

Written by

Connie Yang
Professional tech editor

Approved by

Jessica Shee


What are USB Ports And How Do You Use Them?

Summary: This post is about the definition and appearance of USB ports and their uses. Besides, it will also help you out the differences between USB-A, USB-B, and USB-C.

USB ports

What is a USB port used for?

A USB port is a cable, connector, and protocol connection interface on computers, peripherals, and other electronic devices. USB, short for Universal Serial Bus, is an industry standard for data communication within a limited distance.

A USB port enables USB devices to be connected to each other directly or via a USB cable (on most occasions) to transfer data or supply power.

Which devices have a USB port?

Nowadays, all computers are equipped with at least one USB port. And there are a variety of peripherals designed with USB ports for connecting to your computer.

  • USB flash drives
  • Smartphones
  • External hard drives
  • Digital cameras
  • Mouse & keyboard
  • Printer

What types of USB ports are there?

Different USB devices come with different types of USB ports. And each type of USB port is connected through a corresponding USB connector or cable.

Commonly, there are four types of USB ports.

The types of USB ports

  • USB-A (Type A): Mainly used for wired mice and keyboards and USB sticks.
  • USB-B (Type B): USB-B port is usually not used on modern computers. But it is commonly found on printers, routers, and scanners.
  • USB-C (Type C): It is the new standard for replacing USB-A and USB-B. And it is designed better for thinner devices, like MacBooks, iMacs, and mobile phones.
  • Micro USB: Both USB-A and USB-B have micro versions. They are more used on mobile devices.

Moreover, there are also some uncommon USB ports, such as USB-B Mini, Lightning, etc. If you want to connect a device with an unsupported USB port, use a USB port adapter.

What is the difference between USB-A, USB-B, and USB-C?

Type A, B, or C of USB only refers to the physical design (Or shape) of the ports and connectors.

USB-A is in a flat and rectangular shape. USB-B has multiple designs, but the common shape is a bit squarer. And the design of USB-C is a smaller rectangular with rounded corners.

No matter it's a Type A, B, or C USB, only the USB versions can determine the data transfer speed of the USB cable. All three types of USB ports can run USB versions 1.1, 2.0, 3.0, or 3.1. The higher the USB version is, the faster the speed it brings.

The speed of different USB versions

USB not working, what should you do?

If you insert a USB device into your computer but find it's not working, the first thing you can do is restart your computer. That is to check if the computer appears temporary bugs during the process to recognize the USB device.

If it fails to fix the issue, then, you can:

  • Check your USB port or USB hub (if had).
  • Change the USB cable.
  • Try the other USB port on your computer or plug in a different USB device.
  • Reset SMC if you are using a Mac. Or open the device manager to scan for hardware changes and disable and re-enable the USB controller if you have a Windows PC.