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USB is a plug-and-play interface that lets a computer connect with components and other devices. USB-connected devices cover a wide range from keyboards to music players and flash drives.
USB is also used to transmit power to certain devices, such as smartphones and tablets, as well as charge their batteries. USB version 1.0 was first released in January of 1996, which was quickly adopted by companies like Compaq, Intel and Microsoft.
USB Ports Location
All modern computers have at least one USB port. Here are the typical locations where you can find a USB port on a computer:
- Desktop computer – has 2 to 4 ports at the front and 2 to 8 ports at the back.
- Laptop computer – has between 1 and 4 ports on the sides of the laptop.
- Tablet – has 1 port which is the same as the charging port, while some may have an additional port at the side.
- Smartphone – uses a USB port to charge the battery, which can also be used as a USB port when not being charged.
Millions of different USB devices can be connected to the computer. Some of the most popular USB devices are categorised and listed below:
- Human Interface Device
- Mass Storage
- Thumb drive
- External drive
USB Transfer Speed
- USB 1.x provides a transfer rate of 12 Mbps and is capable of supporting up to 127 peripherals.
- USB 2.0 provides a transfer rate of up to 480 Mbps or 60 MBbs. It is also known as hi-speed USB and was introduced in 2001.
- USB 3.0 provides an enhanced speed and performance from the USB 2.0 including power management and bandwidth. It is also known as SuperSpeed USB and was first made available in November 2009, but the first certified devices weren’t available until January 2010.
- USB 3.1 provides a transfer rate of up to 10 Gbps. It is also known as SuperSpeed+ and was made available as in July 2013. It is the latest version of USB and mostly used by many devices now due to its enhanced performance and speed.
USB Connector Variations
USB connectors come in many shapes and sizes like:
USB Cable Length
USB cables come in multiple lengths, from around 3 feet to just over 16 feet in length.
|Device||USB Cable Maximum Length (in feet)||USB Cable Maximum Length (in meters)|
|High-speed devices||16 feet and 5 inches||5 meters|
|Low-speed devices||9 feet and 10 inches||3 meters|
These maximum lengths are set to take into consideration data transfer timing as well as the risk of losing data when transmitting through longer USB cables. However, USB hubs can be utilised to join two USB cables together and prolong the distance between the two devices being joined.
USB Cable Types
Since there are different transfer speeds for USB, there are also different types of USB cables to work with those transfer speeds.
- USB 2.0 cable is compatible with a device using USB 2.0
- USB 3.0 cable is compatible with a device using USB 3.0.
There are USB extension cables that can join to one end of a USB cable to prolong the length of the cable. It is not recommended to use the extension cables beyond the maximum length limit unless using a USB hub.
USB Flash Drive
USB flash drive is a plug-and-play storage device. It is also known as USB stick, USB thumb drive or pen drive. It is portable and lightweight. It replaced CDs for storage and backups.