wpgraphql: Node & Global ID

https://www.wpgraphql.com/docs/wpgraphql-concepts/ 

Every object in WordPress is treated as an individual "node" in GraphQL. Posts are nodes. Pages are nodes. Categories, tags, users, comments, menu items, etc are all considered "nodes".

And each "node" in the Graph can be identified by a unique ID.

In WordPress, IDs are not truly unique. There can be a Post with ID 1, a User with ID 1, a Category with ID 1 and a Comment with ID 1. WPGraphQL generates opaque global IDs for entities by hashing the underlying loader type and the database id. So, objects loaded by the Post loader get a global ID of base_64_encode( 'post:' . $database_id );. So, a Post with the database ID of 1 would have a global ID of cG9zdDox.