IWCL (IntraWeb Component Library) refers to the IntraWeb components which do the rendering from IWML to HTML and handles communication with the server side components of IntraWeb or other server based components such as user handlers, or REST servers.

IWCL is the core library used by all IntraWeb language editions and is written in TypeScript, a superset of JavaScript which transpiles to JavaScript files.

Visual classes including controls, layouts and other are documented as IWML tags to avoid duplication of content.