Asp.net is a framework and sub part of .net framework to create web based dynamic application.
Skin files are those files in which we define the common property setting for asp.net controls like button, texbox, label etc.
The extension of skin files is .skin.
When we want to apply same property for all controls in the page then we use default skin. This skin automatically applies to the control which defined in the skin. This type of skin does not contain the SkinId property.
A named skin is applied to those controls in which we pass skin id. A named skin contains the SkinId.
If we want to change the theme dynamically using programming then we have to change it in Page_PreInit event. With the help of following code we can dynamically set the theme:-
Page.Theme = "Client2";
Script manager is used to control the processing of ajax. The major responsibility of script manager is for downloading Microsoft Ajax library down to the browser (client).
Update panel control is just like a container for other control. It defines an area in your page which will be independently partially post back without refreshing the whole page. A single page can have multiple update panels.
Internet Information Service
IIS is web based server which integrates asp.net, wcf and SharePoint services.