USB-C is an all in one connector. It can be used for power (up to 100W), it can transfer data at USB 3.x speed (3GBps +), and supports both audio and video transmission (including HDMI and Thunderbolt).
In other words, if you had a device with USB-C you can connect to different devices using only one cable. Also, because of the form factor, it takes up less internal space, which is a commodity for laptops and tablets.
The problem is that the current crop of scanners, external drives, and other peripherals don't support it yet. So far, only certain smart phones and tablets incorporate USB-C, and even then they may or may not fully support the USB-C standard.
It's like when USB was first introduced over 20 years ago. Major OEMs didn't incorporate USB until there were enough peripherals that supported it. The USB-C A connector (the end that plugs into the computer) form factor is the first major change since USB was introduced.
So I see a lot of people complaining about the Surface Pro not having USB C. Both this model and the new one. I'll be the first to admit that I don't know all of the capabilities of USB C so I'm honestly asking what functionality we're missing. USB ports are used to connect peripherals and any USB C peripheral can connect to the Surface. I understand that USB C can be used to charge/power the device, but personally, I'd rather use the magnetic attachment. I'm sure I'm missing something so if anyone can enlighten me, I'd appreciate it.