USB comes in many shapes and sizes, but USB Type-A connectors are the most common type. They are rectangular in shape and have been widely used for decades. In the official USB specification, USB-A is referred to as “Standard-A”.
What are Type A connectors used for?
A USB Type A port or socket. ARZTSAMUI / Shutterstock.com
USB Type-A connectors are the most common type of USB connection you will find.
You will find USB Type A ports in most modern computers, laptops, game consoles (like the PlayStation, Xbox, and Nintendo Switch), smart TVs, streaming media players, and other devices. These USB Type A ports are also called receptacles.
Devices such as USB drives, mice, keyboards, external hard drives, webcams, digital cameras, game controllers, mobile devices and many other peripherals and accessories often have USB Type A connectors. (often called outlets), which can be plugged into Type A ports.
USB Type-A ports work with all USB versions, from USB 1.1 and USB 1.0 to USB 3.0, USB 3.1 and USB 3.2.
USB Type-A and backward compatibility
When it comes to the Universal Serial Bus (USB) standard, there are two things to consider: the physical form of the connector and the underlying protocol (speed).
USB Type A connectors date back to the original version of USB 1.0 in 1996, although USB did not really become mainstream with USB 1.1 until 1998. However, while Type A connectors have been around since some time they still work with the latest modern versions of USB.
This long-standing standard physical connection helps USB in backward compatibility. If you have a modern computer that supports USB 3 and a modern USB device that supports USB 3, you can connect them with a USB cable that supports USB 3 speeds and get all the speed benefits.
However, if you have a USB 3 device, you can still use that same USB cable to connect it to an older computer that only supports USB 2.0 or USB 1.1. It’ll run at slower speeds, but that same USB Type-A connector lets you plug your device into almost anything.
In other words, you can plug any USB Type-A plug into any USB Type-A port and it will “work”. If the devices are from different generations – if you plug a 20 year old USB drive into a modern PC, for example – they may run slower, but they will work.
Blue USB connectors are often faster
Blue inside this USB Type-A connector indicates that it supports USB 3.0 speeds (probably.) LDprod / Shutterstock.com
USB Type-A connectors and ports supporting faster USB 3.0 speeds often (but not always) blue inside. Type A connectors that only support slower USB 2.0 or USB 1.1 speeds often (but not always) have black inside.
The same goes for ports: USB 3.0 ports often have blue on the inside and USB 2.0 ports often have black on the inside. However, this is not guaranteed.
Type A connectors that support USB 3.0 speeds – those that often have blue inside – have nine pins compared to the four pins on older USB connectors. However, they are still backward compatible and those faster speeds will only work when two USB 3.0 devices are connected to each other. Otherwise, they will use the slower speeds.
USB Type-C is the future
One connector and one USB Type-C port. kontrymphoto / Shutterstock.com
If USB Type-A is still the most popular connector, it’s not the future. The future belongs to USB Type-C, which is already common on new devices.
Some modern devices even have USB Type-A and USB Type-C ports, so they’re compatible with everything. A few are even ditching USB Type-A and only have USB Type-C ports.
You can still use a “dongle” that works as an adapter. For example, a USB-A device can be plugged into a Type-A-Type-C dongle, allowing you to plug it into a USB-C port. It works because under the difference of physical connection, USB is still compatible.
USB-C cables are smaller and eliminate the need for mini USB ports and Micro-B connectors. These are other smaller USB connectors that were used to connect USB Type-A devices (like laptops and chargers) with smaller devices (like smartphones) that didn’t have room for a USB receptacle. Full Type-A. With USB-C, there will only be one standard USB Type-C port for all devices. Once it becomes widespread, you will no longer need different types of USB cables for different devices.
USB Type-A will be sidelined by USB4
This dongle allows you to plug a USB Type-A connector into a USB Type-C socket. Mohd Syis Zulkipli / Shutterstock.com
The smaller USB Type-C connector will actually be required by the next USB standard, USB4.
But, although the shape of the connector changes, the underlying USB standard is still backward compatible with devices of previous USB standards.
You will still be able to plug an old USB Type-A device into a future USB4 device that only has Type-C sockets. You will just need a dongle which will convert the physical USB Type-A connection to a USB Type-C connection.