On the 21st day of the A2Z Challenge 2019, I shall talk about A2Z of USB (Universal Serial Bus).  It is a common interface that connects peripheral devices such as keyboards, mice, printers, scanners, media devices, digital cameras, flash drives, and external hard drives. In simple terms, it’s a newer version of a port that helps to connect these devices to a computer. A port is a slot on the motherboard through which you can connect external devices to a computer.

Two great features of the USB are PnP (Plug-and-Play) support and hot swapping. PnP allows the OS to spontaneously discover and configure a new device, without restarting the computer. Hot swapping allows the OS to remove the device without restarting the computer.

A2Z of USB: Types of USB

• Type – A: This is the standard rectangular interface that you find on one end of most the USB cables. This end is used for connecting the device to the PC. Laptops and desktops are equipped with multiple USB Type-A ports.
• Type – B: The interface looks like a square. This is mainly used for printers and scanners to connect them to the PC.
• Mini-USB: This interface was previously used for connecting mobile phones and tablets to a PC
• Micro-USB: Modern day mobile phones and tablets have moved to Micro-USB standard.
• Type – C: This is the newest type of USB standard and is gaining popularity in mobile phones and tablets. It is a reversible cable and promises faster data transfer than its predecessors.

A2Z of USB: Standards of USB

• USB 1.x: Also called Full Speed USB. This was the original standard. Maximum data transfer rate- 12 Mbps.
• USB 2.x: Also called High Speed USB. This includes many modern day USB functions like support for Mini and Micro USB, OTG Cables, pen drives and other USB devices. Maximum data transfer rate- 480 Mbps.
• USB 3.x: Also called Super Speed USB. This is latest version of USB. Latest computers and USB devices include support for USB 3.x. Maximum data transfer rate- 10Gbps. (1Gbps = 1024Mbps)