How much faster is USB-C compared to previous generations of USB, to SATA, and to Thunderbolt™?

USB 3.1 Type-C delivers a 10Gbps data transfer rate. This makes it more than 20 times faster than USB 2.0 and twice as fast as USB 3.0. It is also faster than the 6.0Gbps rate of the SATA III standard, allowing external hard drives to exceed the current speed of internal drives! The 10Gbps speed is the same as that of Thunderbolt, but it is half the speed of the 20Gbps offered by Thunderbolt 2. However, the cost of USB-C is about a quarter of that of Thunderbolt 2, giving it a lower cost/performance ratio, making it well suited for consumer applications.