The Universal Serial Bus (USB) port on a personal computer or laptop allows you to interface with external devices such as keyboards, mice, printers, cameras and scanners. Three major versions of USB have been released since the mid-1990s, with each version offering improved performance over previous releases. If you don't know which version is supported by a USB port on your computer, you can find the information using common operating system utilities on both Windows and Mac systems.
Identifying USB Version on Windows
If you have a laptop or tower computer that runs Windows, you can use the Device Manager utility to find the answer. To find the Device Manager, open the Control Panel and enter Device Manager in the search field. After you locate and open the Device Manager, search the list of devices for Universal Serial Bus controllers. Click on the arrow or plus sign next to the entry to expand the list of USB ports on the computer. Ports marked as Universal Host support USB 1.1, while those marked as both Universal Host and Enhanced Host support USB 2.0. Ports with the term USB 3.0 in their name support USB 3.0.
Identifying USB Version on a Mac
To determine which version a USB port supports on a Mac computer, hold down the Option key on the keyboard while you click on the Apple menu. Select either System Information or System Profiler to view a list of the Mac's hardware. Select USB from the list to expand the USB Device Tree. The version of each port is shown along with the information about connected devices.
Importance of the USB Standard
The introduction of the USB standard grew from the difficulty personal computer users had when connecting new devices. In the early 1990s, computers were manufactured with a variety of different slots and sockets in the back for connecting peripheral devices. Each class of devices used a different type of interface. Keeping track of the cables, connectors and ports for serial, parallel, mouse, keyboard and Ethernet connections was difficult for even the most advanced users.
Another problem with early personal computers had to do with the software that runs peripheral devices. When using a device for the first time, users were required to load software that operated the device, known as a driver. Most devices came with a disk containing driver software that had to be installed before the device could be used. For many users, the installation process for new drivers was error prone and frustrating.
A group of companies, including chipmaker Intel, addressed this connectivity issue by developing the Universal Serial Bus (USB) specification. This standard interface allows a variety of devices to connect using the same socket. It also allows a standard set of drivers to be used. The USB interface came to be known as plug and play since it allows devices to be plugged in and used without loading a driver and restarting the computer.
Release of USB Version 1.1
In 1998, the first published version of USB was published. Known as Version 1.1, this early USB design supported two transmission modes: low speed (1.5 megabytes per second or Mbps) and full speed (12 Mbps). The full speed offered a significant enhancement over the speed of serial ports that had previously been used for tasks such as transferring digital photographs or digital music. Within a few years, however, the increase in high-speed data storage devices created a demand for even faster connectivity on personal computers.
Introduction of USB High Speed
A faster version of USB was introduced in 2000. USB 2.0, also known as Hi-Speed USB, provides data transfer rates of up to 480 Mbps, which is 40 times faster than USB 1.1 Full Speed. In 2007, an additional battery-charging capability was added to USB 2.0 to cover the growing demand for quick and portable device-charging solutions. Using the USB 2.0 port for both transferring data and battery charging was quickly adopted by mobile phone manufacturers, reducing the need for specialized chargers for different types of phones.
USB 3.0 Delivers Super Speed
In 2008, even faster data transfer became available with the release of USB version 3.0, offering speeds of up to 4.8 gigabytes per second (Gbps). This is a tenfold speed increase over USB 2.0. The higher speed was achieved through some fundamental design changes, including the introduction of an additional data bus. This extra wire requires USB 3.0 cables to have a larger connector, making them incompatible with the USB 2.0 port.
USB 2.0 vs. USB 3.0 Cables
When compared side by side, the differences between a USB 2.0 and USB 3.0 cable are apparent. The USB 3.0 cable is thicker and the connector is larger to accommodate extra pins that enable higher data transfer speeds. To make the difference even more obvious, some USB manufacturers make the inside of USB 3.0 connectors blue to indicate the version. However, this is not part of the USB standard, and a manufacturer can make a USB connector black, white or any other color.
USB Connector Compatibility
There are a few different types of connectors for USB cables. The Type A connector is the rectangular flat end that plugs into a USB port on a computer. The other end of the cable has a Type B connector that connects to a device. The Type B connector is smaller than the Type A, and its shape is determined by its purpose. The so-called Mini-B connector, which is small and square, is typically used for digital cameras. The flat Micro-B connector is used for mobile phones.
The same Type B connectors can be used with both USB 1.1 and USB 2.0 devices. Older Type B connectors can also be used with a USB 3.0 plug, but the reverse is not true. A USB 3.0 Type B connector can only be used with a USB 3.0 plug. There is no need to perform a USB 3.0 check before trying to connect a USB 3.0 cable's Type B connector because it does not fit in a USB 1.1 or USB 2.0 port.
For optimum performance, Apple and other computer manufacturers recommend connecting your fastest devices to a computer's fastest USB ports. When you connect a slow device to a fast port, the performance of the device doesn't improve. For example, connecting a USB 2.0 mouse to a USB 3.0 port does not give your mouse the performance of a USB 3.0 device.
The USB Future
A new type of connector known as USB-C was introduced in 2014. One of the most important goals of the USB-C design was to reduce the proliferation of different Type B connectors. A USB-C cable has a connector that is slightly larger than the Mini-B, and both ends of the cable have the same connector. For convenience, the connector is reversible and can be inserted with either side facing up.
Data transfer speeds for USB-C are 10 Gbps, more than double the transfer speed of USB 3.0. Unlike earlier USB versions that could only provide power through a USB-A connector, the USB-C connector can be used for both data transfer and providing power. USB-C ports are available on some versions of MacBook and MacBook Pro computers and on Window 10 computers.