REST stands for "Representational State Transfer". The term is used to describe a class of system architectures, notably the modern day web support by HTTP version 1.1.

The term was defined at some length in Roy Fielding's thesis Architectural Styles and the Design of Network-based Software Architectures.

TiddlyWeb is only partially compliant with REST principles so it is perhaps best to say that it has an HTTP or "web" API. Notably TiddlyWeb does not make an effort to meet the HATEOAS constraint.