IntraWeb/TypeScript like all IntraWeb 17 language editions are built around IWCL which uses TypeScript.
The IWCL by itself with a minor tooling can be used to build fully functional web applications against existing REST servers, WordPress handlers, node, or other server technologies.
The development tooling which will support usage of IWCL independently, or within other IDEs such as Visual Studio and Visual Studio code is known as IntraWeb/TypeScript and is a superset of IWCL which consists solely of the run time libraries.
In addition to IntraWeb/TypeScript edition being useful as a standalone product, it is also used to develop new IWCL components. IntraWeb/TypeScript allows complex custom browser side code to be developed and works in conjunction with a server side language such as IntraWeb/Delphi or other language.