A beginner's guide to USB-C cables

A beginner’s guide to USB-C cables

Since they first entered our lives, mobile phones have always been supplied with cables.

Initially, these were purely used to replenish the battery.

Then, as dumb phones gave way to smartphones, cables became a way to transfer media files.

Over time, the emergence of the Universal Serial Bus standard enabled a single cable to perform both functions simultaneously.

The first USB standard emerged in the late 1990s, but took off in 2011 when USB-A 3.0 arrived, delivering superspeed data transfers of up to five gigabits per second.

However, despite still being used everywhere from car dashboards to plug sockets, USB-A has always retained a couple of drawbacks.

Firstly, it’s not reversible. Nine pins of varying size sit on a solid base which can only be inserted one way up – and it’s not always clear which way.

Secondly, USB-A is relatively bulky.

Neither of these accusations can be levelled at USB-C cables, which were introduced in the early Noughties and are now becoming the default method of connecting our smartphones.

Now C here

As the third iteration of USB connectivity, USB-C cables have evolved to tackle the drawbacks of the rectangular USB-A and the largely square USB-B cables.

Firstly, they’re fully reversible. It doesn’t matter which way the rectangular plug is inserted, because the pins are centrally mounted inside their metal housing.

Secondly, USB-C cables are much smaller, making them easier to store and transport.

Thirdly, the symmetrical alignment of internal pins makes them easier to click into place than other cables, with no screws, clips or thumb-turns required.

However, the greatest advantage is performance-related.

A USB-C cable typically transfers 15W of power and can transmit data at ten gigabits per second – more than enough for high-speed transfers to and from other devices.

Because these cables are developed by the USB Implementers Forum, they also provide a universal standard, though performance does vary from one device and cable to another.

There are over 700 members of the USB-IF consortium, including the likes of Microsoft and Apple, Dell and Samsung.

They’ve collectively decided in recent years to deprecate the array of older USB ports – Mini-A and Mini-B, Micro-A and Micro-B – in favour of the one-size-fits-all C.

The latter is now approaching a level of ubiquity deserving of its name, for the first time in the 25-year history of the Universal Serial Bus.


You may have heard about Thunderbolt connectivity, which is often mistakenly assumed to be proprietary hardware used by Apple.

In fact, Thunderbolt was developed by chip manufacturer Intel, to turbocharge data transfers.

The most recent Thunderbolt 3 connector blends standard USB and power connections with data transfers up to 40Gbps – four times faster than standard USB-C sockets.

However, there are no incompatibilities here. A USB-C cable will fit in a Thunderbolt port and vice versa, though they’ll be limited to the top speed of their slowest component.

Today, it’s rare to find an Android smartphone which doesn’t use USB-C, though Apple (despite contributing to the USB-IF) favour their non-reversible Lightning cables.

Back To Top