TLDR: Since 2010, UK passports have been biometric ePassports containing a chip for added security and eGate use, identifiable by a golden camera icon on the front cover; all valid UK passports include this chip.
NFC Passports
Since 2010 UK passports have been ePassports, also known as biometric passports. They contain a chip in the front cover confirming the passport details, as an extra layer of security. It also allows you to use eGates at airport security.
Any in-date UK passport will have a chip.
You can tell if a passport has a chip from the small golden camera icon at the bottom of the front cover. This applies to UK and international passports.