Hey Questers,

Lets have Quick information about the usb 2.0 and 3.0 and discuss about speed and performance.

What is USB ?

USB (universal serial bus) is the standard used to connect peripherals -- flash drives, keyboards, mice, cameras, phone chargers, etc. -- to computers and adapters. It is also used to transfer data between devices, such as between flash drives or external hard drives and computers

USB 2.0 VS 3.0 

Now we'll look at the USB 2.0 and USB 3.0 speed. They also differ in design and a few other ways.

• Speed : USB 2.0 offers a transfer rate of about 480 Mbps, whereas USB 3.0 offers a transfer rate of about 4,800 Mbps which is equal to about 5 GB. This super-fast transfer speed of USB 3.0 can be especially useful when backing up or transferring large amounts of data, such as an external hard drive.

• Connector Wires -- USB 2.0 has four connector wires, whereas USB 3.0 has nine, which increases speed and bandwidth.

• Power Output and Efficiency -- USB 3.0 brings more power and operates at improved power efficiency than its older counterpart.

• Backward Compatibility -- USB 3.0 ports are also totally backward compatible, which means they will work with other USB versions, including 2.0
• Interior Color -- To tell the difference between these two technologies with a quick glance, look for a black or blue block inside the port. The black interior indicates USB 2.0, while the blue one indicates 3.0

So Which Is Best, USB 2.0 or USB 3.0?

It's safe to say USB 3.0 out performs USB 2.0 in every category that matters. However, it may come at a price. As you might expect, you will pay more for USB 3.0 devices than USB 2.0 devices, so it's important to figure out if you actually need the faster option for your specific application. If you're not working with a huge amount of data, there's no reason to pay extra for the faster speeds.

Source : Usb memory  

Thanks

@Naveen Yerradla