The most widespread style of web API, where data is exposed as addressable resources and manipulated with standard HTTP methods — GET to read, POST to create, PUT or PATCH to update, DELETE to remove.
REST is understood by every platform, cacheable by default, and simple to debug with ordinary tools. For most products it is the lowest-risk choice, and almost every third-party service you integrate with speaks it.
We design resources around the business domain, not the database tables, version the API from the first release, and publish an OpenAPI specification so clients can generate typed code instead of guessing.