USB 2.0 vs USB 3.0
USB stands for Universal Serial Bus. It's an industry standard that establishes specifications for cables, connectors, and protocols for connection, communication and power supply between personal computers and their peripheral devices.
It released in 1996.
USB was designed to standardize the connection of peripherals like keyboards, pointing devices, digital still and video cameras, printers, portable media players, disk drives and network adapters to personal computers, both to communicate and to supply electric power.
It has largely replaced interfaces such as serial ports and parallel ports and has become commonplace on a wide range of devices. USB connectors have been increasingly replacing other types for battery chargers of portable devices.
The USB standard is currently maintained by the USB Implementers Forum (USB IF). There have been three generations of USB specifications: USB 1.x, USB 2.0, USB 3.x.
USB3.0 was released in November 2008, almost eight years after the release of USB 2.0. Over five years later, in 2014, USB 3.1 was released with widespread use expected in 2015.
USB2.0 vs USB3.0
USB 3.0 is a newer version of the USB port.
The USB 2.0 version is generally less expensive than its USB 3.0 version.
USB 3.0 provides better speed and more efficient power management than USB 2.0.
USB 2.0 has a data transfer rate of 480 megabits per second (Mbps).
USB 3.0 has a data transfer rate of 4,800 Mbps. This means that a USB 3.0 is approximately 10 times faster than USB 2.0.
USB 3.0 devices are backward compatible with USB 2.0 ports.
USB 3.0 is capable of delivering more power when the need arises and conserve power when the USB drive is connected but not being used.
USB 2.0 is capable of providing up to 500 mA current.
USB 3.0 is capable of providing up to 900 mA current.
USB 2.0 offers a one-way communication path. USB 2.0 can only send data or receive data at a given time, but not do both.
USB 3.0 uses two separate unidirectional data paths. USB 3.0 can simultaneously send and receive data.
USB 2.0 has 4 connector wires whereas USB 3.0 has 9 connector wires.
USB 3.0 receptacles are electrically compatible with USB Standard 2.0 device plugs if they physically match.
USB 2.0 is smaller in size, whereas USB 3.0 has extra space for more wires.
Maximum cable length for USB 2.0 is 5 meters, and for USB 3.0 is 3 meters.
In USB 3.0, a new feature was added (using packets NRDY and ERDY) to let a device asynchronously notify the host of its readiness.
The USB 2.0 is black in color, USB 3.0 is blue and USB 3.1 is Red in color. It has been adopted as an international standard. So, wherever you purchase any of your computer parts, these colors should be the same.
The USB 3.0 version is generally more expensive than its USB 2.0 version.
Stock photo from Hsynff