Elements in a web.config File

  
		
<configuration>
	In a Web.config file, all the configuration information for an
	ASP.NET application must reside between the 	<configuration>
	and </configuration> tags. This is the root node, which contains
	the declaration of all other 	sections of the Web.config file.
<appSettings>
	This section of the Web.config file provides a way to define
	custom application settings for an application. The section
	can have multiple <add> subelements.
	<appSettings>
		<add key="connectionstring" value="localhost;uid=readonly;pwd=user"/>
	</appSettings>
<compilation>
	 This element sets several compilation settings for the
	 application. Some of the settings involve setting a default
	 language and debug option for the application setting. Debug
	 pages are larger and execute more slowly, so you should use them
	 only for testing purposes. This section also provides support for
	 the <compilers>, <assemblies> , and <namespaces> subelements.
<namespaces>
	This subelement is used to add or remove namespace references for
	assemblies that must be made available when compiling Web pages.
<authentication>
	 The <authentication> element sets the authentication policy for
	 the application. Possible modes are "Windows," "Forms,"
	 "Passport," and "None."
<pages>
	The <pages> element allows configuration of page  application
	specific settings.
<customErrors>
	The <customErrors> element provides a means for defining custom
	error messages 	for an ASP.NET application. This is generally
	used to point users to a 	friendlier message than the default
	error messages. The <customErrors> element 	section supports
	multiple <error> subelements that are used to define custom errors.