What is GraphQL?
GraphQL is a query language and runtime for APIs where the client specifies exactly which fields it needs in a single request, instead of hitting multiple fixed REST endpoints. This avoids over-fetching and under-fetching data, at the cost of more complex server-side query resolution and caching.
Example
{ user(id: 42) { name email } } requests only the name and email fields.
Related tool
Try it on ToolSphere — runs entirely in your browser, nothing is uploaded to a server.