It all comes down to cables: the more expensive 6P has a USB Type-C to USB Standard-A cable included, whereas the more affordable 5X offers a USB Type-C to Type-C one instead.
In plain English that means you can't plug your Nexus 5X into a standard USB port without buying another cable. You can plug it into machines with the new USB Type-C standard, including the latest MacBook and the second generation Chromebook Pixel.
Hidden costs
Both phones come with plug adaptors so there's no problem on that score: you can of course charge your Nexus 5X phone with what's in the box. It's just phone-to-computer connections that might need an extra bit of kit, if you're buying the Nexus 5X.It's not a major problem - you may never have to plug your Nexus into your laptop anyway - but don't forget to factor in the potential cost of an extra cable if you have your heart set on the Nexus 5X.
The new USB Type-C standard appearing on phones, computers and just about everything else offers faster charging times, faster data transfer speeds and the ability to do two jobs at once (like putting your laptop display on a big screen while charging it at the same time).
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