• Beltsville News

Tech Sense: The USB Port

The USB Port

As I see it part of the purpose of this column is to give the readers insight into technology. This month I thought I would write about a small piece of technology that has become ubiquitous, but few really understand, the USB Port. USB stands for Universal Serial Bus. It was first created in 1996 to provide a common means to connect peripherals, like keyboards, mice, and printers to personal computers.

USB 1.1 the first widely accepted version of the standard started to appear on computers in 1998. USB 1.1 supported two speeds 1.5 Megabits per second and a faster 12 Mbps speed that was useful for connecting to disk drives and thumb drives. Before USB there were different ports on the computer for printers and cameras (parallel port), mice and keyboards (PS/2 ports), modems and other computers (serial ports), and external storage devices like hard drives (SCSI ports). If you didn’t have a certain port you typically needed to purchase an adapter and install it inside the computer. USB simplified this because many different devices could all now use the same port. A single USB port could also be extended using a USB Hub to add many additional ports to a single port. Devices on the USB did not need any special configuration and many classes of devices for example “Human Interface Devices” like mice and keyboards did not even need device drivers. This made USB devices mostly “plug-and-play”. USB 1.1 also had one additional important feature, it could detect PS/2 keyboards and mice connected through a passive adapter and support hos protocols. This eased the transition between PS/2 devices and USB devices.

In the early days of USB there were only two types of connectors: USB Type A and USB Type B. The USB A connector is rectangular with a black bar inside and typically plugs into the computer or host device. The USB connector is more squared with two corners cut off and a square hole in the center.

USB 2.0

USB 2.0 was released in 2000 and added several new connectors; the mini A, mini B, and mini AB followed later by the micro A and the micro B connectors. The mini-connectors were smaller to connect with smaller devices like cameras and the later micro connecters were even smaller but were also more reliable. The mini-A and mini-AB connectors were quickly retired leaving only the mini-B and the newer micro connectors. The micro-B connectors are still commonly used to connect and charge cell phones.

USB 2.0 increased the bus speed to be faster supporting speeds up to 480 Mbps and added support to for device charging and increased the amount of power that could be provided to run an attached device.


The USB 3.0 standard was released in 2008. It added a SuperSpeed feature that increased throughput to 5 Gigabits per second with practical speeds of 3.2 Gbps. USB A connectors on the computer that support this have blue plastic bars showing on the inside. USB 3.0 also added the USB Attached SCSI Protocol (UASP) supporting higher speed connections with storage devices. If you purchase a USB storage device like a backup hard drive make certain it supports UASP, the speed difference is significant. USB 3.0 also added a special USB Micro-B SuperSpeed connector with a wider plug.

USB 3.1 added a SuperSpeed+ transfer mode that double the transfer rate of the normal SuperSpeed mode.

USB 3.2 doubles the transfer rate again over the fastest USB 3.1 transfer mode and supports the new reversible USB C connector.


The new USB 4 standard was released in 2019 supporting 40 Gbps throughput and adds support for Thunderbolt 3 protocols, Display Port, and Computer to Computer connections. Display Port support allows displays to be driven directly by output over a USB C cable. This means a single type of port can be used for all of your connections including audio and video output.

TLDR (too long didn’t read)

Ok, I know this might have been pretty dense, so let me summarize. USB has been making connecting things to your computer easier for years. The faster USB connections will have a blue piece of plastic visible in the type-A connector. These are better and much faster than the older black type-A connectors. Prefer external disk drives that can support these faster connections and the UASP protocol. USB type C connectors are the future, are easier to use, are reversible, and way faster. Newer phones use these smaller type C connectors, older phones tend to use the micro type B connectors. Computers usually expose a mix of black and blue type-A connectors. Use the black ones for slower devices like keyboards and mice. Newer computers also expose type C connectors. These type C connections are normally the fastest.

Next Month

Next month we will get a head start on world Change Your Password Day.

2 views0 comments
Right Click Disabled
Beltsville News Logo_Gold.png