Okay kiddo, so the Pen Pinter Prize is an award given to somebody who writes really good things like books, poems or plays. It's named after a man called Harold Pinter who was a very famous writer himself.
Lots of people who write things can be nominated for this award, and a group of clever people called judges read all of the things that the people have written and decide who they think is the best.
The person who wins the prize gets to have a fancy ceremony where they are given a nice trophy and some money too. They are also invited to give a special speech, just like the ones that Harold Pinter used to give, where they can talk about why writing is important and how it can help people understand the world around them.
So basically, the Pen Pinter Prize is a really cool award given to someone who writes really well, and it's named after a guy who was also really good at writing.