What is Euro NCAP and how does it relate to the Audi A3?

I've heard people talking about the Euro NCAP, but I'm not sure how it relates to the Audi A3. Can someone explain?

According to Euro NCAP, the Audi A3 has a 5-star safety rating, which means it excels in crash protection, safety assist technology, and child occupant safety.

It's a car safety performance assessment program based in Europe. It’s adopted by several European countries and replicated with the same name and protocol in non-European countries as well.