Any project has three parts three is the standard and common part and the other is the customized version. In ASP.NET they have three types of pages for any project three is common ASPX pages and the other is customized ASPX pages. Common pages are stored on file directories while customized versions of pages are stored in content database.
So in other words, we need an abstract mechanism by which we can make the content pages of SQL Server database and virtual directories. This is accomplished through virtual provider provided by SharePoint. So for every page reads custom virtual provider of database content and the same thing happens with the ASP.NET runtime. Common for all pages goes to the directory, parses it and passes it in the ASP.NET runtime.
virtual provider is an abstraction that loads the page from the bottom or the file system depending on whether or common custom pages and so with the ASP.NET runtime.
