GraphQL (gql) is a query language, as is Structured Query Language (sql).
The purpose of sql is to retrieve data stored in a database system efficiently, while gql enables a web client to retrieve data from a server efficiently.
sql statements are generally written and called by backend systems, whereas gql statements are generally written and called by client systems.
REST APIs have various endpoints because they combine URLs, methods, and other elements. gql has a single endpoint.