Codes are mandatory - if you use 3 digits codes as above, this will make entry by code easy.

English UK Territory and Country are used in the English UK Statistics.
If you need to prepare English UK Statistics, it is well worth the effort to set these up correctly as Class can then prepare a completed Excel spreadsheet directly for submission to them.

ISO Code
May be required when making electronic submissions to the UKBA.
These codes can be checked at:
http://unstats.un.org/unsd/methods/m49/m49alpha.htm

EU Indicator
The list is best if it shows the European countries (EU/EEA) that are Visa exempt.