What is USB? Technological Enhancements Explained!

      USB stands for Universal Serial Bus. It is an industry standard specification for connectors, cables and protocol for connection, communication and power supply. It was first introduced in 1996 and its standards are maintained by USB-IF or USB Implementers Forum. This USB technology itself received many technological enhancements over times since its introduction. Sometimes implementers enhances in its data transfer speed, sometimes enhances its sizes, sometimes enhances in its power supply capacity. It is now available in various types and various standards.


Types - 


      USB has many different types. These variations appears due to physical dimensions and technological aspects, in terms of data transfer speed and power supply. Based on the speed and power supply ability USB has four types -

i. USB 1.0          ii. USB 2.0           iii. USB 3.0        iv. USB 3.1       v. USB 3.2         vi. USB 4.0 


Based on the physical form, USB has three types -

i. USB - A          ii. USB - B         iii. USB - C




USB 1.0 -


The first generation USB, USB 1.0, was introduced in 1996. It has the data transfer speed range 1.5 MB to 12 MB. It has maximum data transfer rate of 12 Mbps and maximum power output of 2.5V/500 mA with the power direction from host to peripherals. It comes with two types of cable connections i.e Type A  to Type B.


USB 2.0 - 


The second generation USB technology introduced in the year of 2000 which was the data transfer rate and power supply enhancement over USB 1.0. It has maximum data transfer rate of 480 Mbps and maximum power output of 2.5V/1.8A with the power direction from host to peripherals. It comes with two types of cable connections i.e Type A to Type B.


USB 3.0 - 


The third generation USB technology introduced in the year of 2008 which was the data transfer rate and power supply enhancement over USB 2.0. It has maximum data transfer rate of 5 Gbps and maximum power output of  5V/1.8A with the power direction from host to peripherals. It comes with two types of cable connections i.e Type A  to Type B.

USB 3.1 - 

The USB 3.1 technology introduced in the year of 2015 which was the data transfer rate and power supply enhancement over USB 3.0. It has maximum data transfer rate of 10 Gbps and maximum power output of  20V/5A with the bi-directional power direction. It comes with two types of cable connections i.e Type A  to Type C and both the reversible Type C ports.

USB 3.2 - 

The USB 3.2 technology introduced in the year of 2017 which was the data transfer rate and power supply enhancement over USB 3.1. It has maximum data transfer rate of 20 Gbps. It comes with two types of cable connections i.e Type A  to Type C and both the reversible Type C ports.

USB 4.0 - 

The USB 4.0 technology introduced in the year of 2019 which was the data transfer rate and power supply enhancement over USB 4.0.. It has maximum data transfer rate of 40 Gbps. It comes with two types of cable connections i.e Type A  to Type C and both the reversible Type C ports

based on the physical dimension, USB connecters also has some variation. they are - 

USB Type - A - 

USB Type - A is the connecter which we connect with our PCs port. It has the connecter cables which contains both way Type - A connecters. It has received enhancements in terms of speed and power supply when USB technologies introduced over the years such as 2.0, 3.0 etc.

USB Type - B - 

USB Type - B has a smaller connecter than USB Type - A. This USB - Type B also has two variants i.e. USB - B Mini and USB - B Micro. USB - B Mini came first after the USB - A and then implementers brought enhancement over USB - B Mini as USB - B Micro, where its connecters gets more smaller than USB - B Mini. These Type - B ports have received enhancements in terms of speed and power supply when USB technologies introduced over the years such as 2.0, 3.0 etc.

USB Type - C - 

USB Type - C gets a huge design enhancement over previous types. It comes with a reversible connecters which has 24 pins. This USB Type - C brought more power supply and data transfer ability. These Type - C ports have received enhancements in terms of speed and power supply when USB technologies introduced over the years such as 3.0, 3.1 etc.

Image Courtesy -

1. www.google.com