Web.config is the main settings and configuration file for an ASP.NET web application. The file is a XML document that defines configuration information regarding the web application.This file stores the information about how the web application will act. The web.config file contains information that controls module loading, security configuration, session state configuration, and application language and compilation settings. Web.config files can also contain application specific items such as database connection strings. Using WebConfigurationManager.OpenWebConfiguration() you can read Web.config file sections in your Web Applications.

Web config is the main settings and configuration file for an ASP.NET web application. The file is a XML document that defines configuration information regarding the web application.This file stores the information about how the web application will act.