What is a USB?
The Universal Serial Bus “USB” 3.0 is the most recent specification of USB standard laid down by Intel. It was released in August 2008, by a group of developers led by Intel. The technology supports the transfer of data at very high speeds – from 625 Megabytes per second up to 5 gigabits per second, which is actually ten times as fast as compared to USB 2.0. When USB technology was first introduced, it was considered to be one of the best things to have ever happened in the field of personal computing, and PC users welcomed it wholeheartedly. Over the years, the USB technology has kept on evolving, and has become more and more effective as well as popular. Many variants of interfacing plugs have been designed and developed by manufacturers to support the technology, and to link various peripheral devices with the PC system. Originally developed to be used by modems and routers, USB now supports a hoard of external devices, which can be attached with the PC primarily for data transfer purposes. However, majority of the devices communicate with PCs through USBs including keyboards, mice, printers, etc. Fundamentally, USBs help to interface or “join” external or peripheral devices with PCs.
Devices using USB technology
Devices which help us to interact with the PC are termed as human interface devices. USB can help these devices to connect with the PC through special sockets specially designed to support their interface. Human interface devices like mice and keyboards need very low bandwidths for communicating purposes, and are very efficiently supported by even USB 1.0. However, external peripheral devices such as printers, fax machines, scanners, hard drives, and backup devices need higher versions of the USB technology. Devices such as cell phones, digital cameras, game counsels, and personal digital assistants (PDAs) also communicate through USBs.
USB versions and speed transfer rates
The USB technology has evolved over the years, and with each new version, it has consistently increased the data transfer rate:
• USB 1.0 supporting low speed up to 1.5 Mbps
• USB 1.1 supporting full speed up to 12 Mbps
• USB 2.0 supporting high speed up to 480 Mbps
• UBS 3.0 supporting super speed up to 5 Gbps
USB 3.0 compatibility with version 2.0
USB 3.0 attains its exceptionally high transfer rates by incorporating four additional wires within its data cable – a total of six wires. It supports full-duplex communication protocol (capacity to send as well as receive data simultaneously over the same medium), and utilizes negligible electrical power. It supports backward compatibility with USB 2.0 version devices. However, to achieve the full benefit of USB 3.0 it is required to use devices compatible with the latest USB version, and its special cable.