HTC One M8 for Windows - Manual (Page 174)

Sharing content with NFC
With built-in Near Field Communication (NFC), you can share content with
people easily just by placing your phone back to back with another phone
that has NFC. Share a webpage you're viewing, contact information, and
more.
Turning NFC on and off
1. Swipe down from the top edge of the screen with one finger.
2. Tap All settings > NFC.
3. Tap the On/Off switches next to the features you want to use.
174 Connectivity