Relay is a framework in ReactJS for declarative data fetching, which solves the problem of updating the data in a React-based application and where exactly it has to be updated. Using GraphQL, the Relay framework decouples what data is to be fetched from how it should be fetched.
GraphQL is like a query language to query a graph though not typically a graph like those represented in pie charts, x, y axes, or Venn diagrams.
It's used to query from a relationship graph, where each node and the relationship between them are represented as edges.
In order to fetch data from a subset of such a relationship-based graph, GraphQL is very useful.
Unlike in representational state transfer (REST) where data is fetched from the server based on server endpoint using resources, in GraphQL data are fetched from the server based on the requirement by the client.
Thus, the data is decoupled, and all the data are fetched at one go from the server within a single network request.
Data can be stored...