The GDPR (General Data Protection Regulation) is a data protection law that regulates how personal data is protected for people residing in the European Union. However, it also extends beyond the EU to include the EEA and while the UK has left the EU, GDPR still does apply and in that country is retained alongside their (UK) domestic law as the "UK GDPR".

For reference,

The EU countries are:

Austria, Belgium, Bulgaria, Croatia, Republic of Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain and Sweden.

The European Economic Area (EEA) is:

The EEA includes EU countries and also Iceland, Liechtenstein and Norway. It allows them to be part of the EU’s single market.

** Switzerland is not an EU or EEA member and doesn't participate in this data protection law.