I have seen a couple videos on GraphQL in the past, but it has been some time. So, in one sense, I am starting fresh.

Here is the first video I watched this evening. It is a very good overview of GraphQL with a nice intro about some of the limitations of REST. https://youtu.be/KoSSlxjTdXk

The video included a link to a site to play around with things at this url:
Here is a good query to start with

{
  allFilms {
    films {
      id,
      title,
      director,
      openingCrawl
    }
  }
}

More to come...