What Is USB-C? An Explainer

With many Mac and Windows laptops now featuring the interface, it's clear that the USB-C connector is here to stay. Here's why that's a good thing.

Truly Universal?

A single standard to rule them all is mostly elusive in the realm of personal technology. At best, there's a format war and one emerges victorious for a few years until an entirely new technology comes along. To wit, VHS ate Betamax but then was replaced entirely by the DVD, which is now facing extinction in the face of Blu-ray, a standard that itself slaughtered its chief rival, HD DVD.

But USB-C is different, perhaps even truly as universal as its acronym (Universal Serial Bus) suggests. It is now found on all manner of devices from simple external hard drives to smartphone charging cables. But while every USB-C port looks the same, not every one offers the same capabilities. Here's a guide to everything it can do, and which of its features you should look for when buying your next USB-C device.

What Is USB-C?

USB-C is the industry-standard connector for transmitting both data and power. The USB-C connector was developed by the USB Implementers Forum, the group of companies that has developed, certified, and shepherded the USB standard. It counts more than 700 companies in its membership, including Apple, Dell, HP, Intel, Microsoft, and Samsung. This is important, because it's part of why USB-C has been so readily accepted by PC manufacturers. Contrast this with the earlier Apple-promoted (and developed) Lightning and MagSafe connectors, which had limited acceptance beyond Apple products, and, because of USB-C, are soon to be completely obsolete.

Is It Like Micro USB?

The USB-C connector looks similar to a micro USB connector at first glance, though it's more oval-shaped and slightly thicker to accommodate its best feature: Like Lightning and MagSafe, the USB-C connector has no up or down orientation. Line up the connector properly, and you don't have to flip it to plug it in. The cables also have the same connector on both ends, so you don't have to figure out which end goes where, which has not been the case with all the USB cables we've been using for the past 20 years.

USB-C and USB 3.1

The default protocol with the USB-C connector is USB 3.1, which, at 10Gbps, is theoretically twice as fast as USB 3.0. The minor wrinkle is that USB 3.1 ports can also exist in the original, larger shape; these ports are called USB 3.1 Type-A. But aside from on desktops, it's much more common to see USB 3.1 ports with USB-C connectors.

The USB Implementers Forum (USB-IF) has defined the USB 3.1 Gen 1 standard as meeting the same interface and data signaling rates as USB 3.0. So when you see USB 3.1 Gen 1, it basically works at the same 5Gbps speeds as USB 3.0. USB 3.1 Gen 2 refers to data signaling rates at 10Gbps, double that of USB 3.0, and matching the speeds of single-channel Thunderbolt.

Port Support

USB-C's support for sending simultaneous video signals and power streams means that you can connect to and power a native DisplayPort, MHL, or HDMI device, or connect to almost anything else assuming you have the proper adapter and cables. (See the next section for more on this.) The USB-C spec even includes audio transmissions, but so far it has not replaced the 3.5mm headphone jack on computers as it has on phones like the Essential Phone PH-1. This and many other high-end Android phones, such as the Google Pixel 2 XL, use the USB-C interface for charging and data transfer instead of their former go-to, micro USB, even if they also include a conventional 3.5mm headphone jack.

Make sure to check the specs on any PC you're thinking of buying, because not all USB-C ports are alike. So far, every one we've seen supports both data transfers and power delivery over USB-C. But while the USB-C standard supports connecting DisplayPort and/or HDMI displays with an adapter, not every PC maker has connected the ports to every system's graphics hardware.

This article first appeared at: https://www.pcmag.com/article2/0,2817,2478121,00.asp