European e-commerce VAT directive
The European e-commerce VAT directive (2002/38/EC from 7 May 2002) is a directive in the European Union which regulates value added tax of sales to consumers in EU and EEA countries. Several third-party tools and plugins have been developed to help online shops comply with the directive by automating VAT rate updates across EU member states, including solutions for platforms such as WordPress.
Source: Wikipedia — European e-commerce VAT directive (CC BY-SA 4.0)