From OpenSCADAWiki
In the requests for the Web resources the URL(Universal Resource Locator) are commonly used. Hence, the URL is passed as the main parameter via HTTP. The first element of the requested URL is used to identify the module UI. For example, the URL "http://localhost:10002/WebCfg" means requesting to the module "WebCfg" on the host "http://localhost:10002". In the case of an incorrect indication of the module ID, or when you address without identifier of the module at all, the module generates the information dialogue on the entry and the choice of one of the available user interfaces. Example of the dialogue is shown in Figure 1.