What is post code?
What do you mean post code?
iPhone 6, iOS 12
Question marked as
Postcode, zip code, Eircode, etc, a code used by the local postal mail system to deliver mail and packages to your location.
https://en.wikipedia.org/wiki/Postcodes_in_the_United_Kingdom
https://en.wikipedia.org/wiki/ZIP_Code
This location code can be used to find a local resource or service provider, too.
What is the context for your question; what are you attempting to do that is requesting a postcode?