USB technology has been around for more than 20 years now. We have become so used to taking it for granted, and we do not consider it special. Although it is almost impossible to never use a USB device or to connect a USB connector to a USB port, you may not know what USB means and what this technology does. You may have heard some acronyms like USB Type C, but that’s pretty much it. In this article, we will explain what USB is, give you some history about this standard and share the differences between the different types of ports such as USB Type C, Micro USB, USB 3.0 and so on. Let’s get started:
What does USB stand for?
USB stands for Universal Serial Bus and represents an industry standard for cables, connectors and communication protocols, used for connection, communication, and power supply between different data processing units. It is used by a wide variety of devices, from the usual keyboard and mouse to cameras, printers, scanners, flash drives, external hard drives, smartphones, tablets, TVs and so on.
Universal Serial Bus is a plug-and-play interface, which means you can connect a device that has a USB port to your computer, and the computer will automatically detect and install the device, but sometimes you need to supply them required the operating system drivers. In order to function as a means of communication, USB can transfer data to and from the devices it connects, such as from the computer to the keyboard and vice versa.
USB can also supply power to devices. This feature is one of the most useful features because it not only enables your devices to communicate between them, but it also lets you power them or charge the batteries in your devices. For example, most external hard drives we use today are powered exclusively through their USB ports, without using separate power adapters. In addition, smartphones have a USB port which is used both for data transfers and for charging the batteries.
History about USB standards
Universal Serial Bus, or USB in short, was designed in 1996 by several important companies: Compaq, DEC, IBM, Intel, Microsoft, NEC, and Nortel.
Before USB was invented, computers used to connect external devices such as keyboards, mice, printers, scanners, cameras, and so on, using various types of ports and connections. For example, before the adoption of USB, keyboards and mice were usually connected via PS / 2 connectors or through serial ports. Printers and scanners are usually connected via parallel ports. And if you were a gamer back in those days, you also needed a gaming port if you wanted to play games on your computer with a joystick or gamepad. Just take a look at the examples from the image below:
The first USB ports were not capable of high-speed transfers, and hardware manufacturers did not embrace this interface right from the start. But a few years after it was developed, the USB interface was revised by the companies that created it, and they made USB version 2.0, which was much faster. Because of that, after the year 2000, the USB port saw a huge expansion, and it is now found on all types of devices. Since then, USB has become the most important way to connect devices and transfer data between them.
USB versions and data transfer rates
Since it was first developed, the USB interface was adopted faster with each revision. Here are the most important revisions or versions of USB:
- USB 1.0 and USB 1.1 – were the first iterations of the USB interface, released in 1996 and 1998, respectively, and were capable of data transfers of up to 1.5 Mbps and 12 Mbps respectively. At the time of their development, USB 1.0 was also known as Low Speed USB , while USB 1.1 was known as Fast Speed USB.
- USB 2.0 – also known as Hi-Speed USB, was released on April 2000 and supports maximum theoretical data transfer speed of up to 480 Mbps. In reality, maximum effective throughput is limited to 280 Mbps or 35 MB / s. USB 2.0 is backward compatible with USB 1.0 and USB 1.1, which means you can use old devices with USB 1.x ports to connect to newer devices that have USB 2.0 ports.
- USB 3.0 – came to life in November 2008 and it is also known as SuperSpeed USB. It can support theoretical data transfer rates of up to 5 Gbps, but the real speed you can get at it is around 3, 2 Gbps or 400 MB / s.
- USB 3.1 – was released in July 2013 and is also known as SuperSpeed + USB. It is capable of theoretical data transfers of 10 Gbps, double of USB 3.0. In reality, the maximum achievable transfer speed is 7, 2 Gbps or 900 MB/s.
How do I differentiate between USB 3.x ports and USB 2.0 ports?
To distinguish USB 3.x ports from USB 2.0 or USB 1.x ports, the USB 3.x ports are usually colored blue. The previous versions of USB – USB 2.0 and USB 1.x – were usually painted black.
Types of USB connectors and ports
There are many types of USB ports and connectors, and before we show you the most common, let’s first see what is the difference between a USB port and a USB connector:
A USB connector is the end of a USB cable that connects to a USB port.
A USB port is a location on the computer or device you are connecting to a USB connector.
Here are the most common USB connectors:
USB Type A – is the most common type of USB connector and port. This type of port is probably found on most computers and laptops. The connection is large and bulky, found at the end of the USB cable you want to connect to your computer. This USB Type A appeared with USB Type B , when the first USB specification was released, in 1996.
USB Type B – probably the largest USB connector out there, USB Type B is square, with two small facets on two of the corners. The USB Type B connector is usually used at the end of the USB cable that connects to the printer, scanner, and other large devices.
Mini USB – are smaller versions of USB Type A and USB Type B connectors. They were introduced in 2000. However, Mini USB connectors are very rare these days as they were outdated by the newer Micro USB connectors.
Micro USB – are even smaller than Mini USB connectors and are the most widely used USB connectors today, especially on smartphones and cameras. They were introduced in 2007.
USB Type C – is the latest version of a USB connector, released in 2014, and is characterized by three things: it is small, it is reversible, and it is usually used for USB 3.1 ports. The USB Type C connector was created at about the same time that USB 3.1 was released, making the common mistake of assuming that USB 3.1 and USB Type C are the same. In reality, they are not, as USB 3.1 is a USB protocol, while USB Type C is a connector specification. Although not very common, some devices can use USB Type C connectors but only support USB 2.0. All things considered, the future is about USB 3.1and USB Type C, so you should expect more compatible devices to be released on the market.