The document summarizes the architecture of Siebel applications, including the components, data flow, and high-level functions. Key components include the Siebel web client, web server, Siebel web server extension (SWSE), Siebel gateway name server, Siebel server, database server, and file system. The Siebel server manages business data and processes requests from clients. It uses a configuration file and repository file to initialize the application. User requests flow from the web client to the web server and SWSE, then to the Siebel components to retrieve and return data.