It is the latest version of Microsofts ASP, a powerful, server-based technology for creating dynamic Web pages. Being a core element in the .NET platform, all .NET languages utilize ASP.NET as their entry point for Internet development. Perhaps the biggest difference between earlier versions of ASP and ASP.NET is the way in which code runs on the Web server. With ASP.NET, code is com- piled into executable classes that are compiled to native code by the common language runtime layer of the .NET Framework. All the earlier versions of ASP supported only scripting languages, which were interpreted. Since ASP.NET pages are now executable classes, they have access to all the other powerful features  of  the  common  language  runtime,  such  as  memory  management, debugging, security, and strong data typing. ASP.NET has built-in support for three languages: Visual Basic .NET, C#, and JScript.NET. The user can install support for other .NET-compatible lan- guages as well. JScript.NET is Microsofts latest version and implementation of  JavaScript. Although  this  version  still  maintains  its  scripting  feel,  it  is fully object-oriented and compiles to MSIL. Because all ASP.NET code must be written in a .NET language, the ASP.NET programming framework is the foundation of Web services and Web Forms, the two components of ASP.NET Application Services. The following list illustrates how developers can exploit ASP.NET in developing Internet-centric applications. nn XML Web services gives developers the ability to access server func- tionality remotely. Using Web services, organizations can share their data and component libraries with other applications. Web services enable client/server and server/server communication through the HTTP protocol by using XML. Consequently, programs written in any language, using a component model and running on any operating system, can access Web services. nn ASP.NET Web Forms gives the developer the ability to create Web pages on the .NET platform. Web Forms enables developers to program embedded controls on either the client or the server. Using ASP Server Controls, Web applications enable the easy maintenance of state as information is communicated between the browser and the Web server. nn ASP.NET and the .NET Framework provide default authorization and authentication schemes for Web applications. Developers can easily remove, add to, or replace these schemes, depending on the needs of the application. nn Simple ASP pages can be migrated easily to ASP.NET applications. ASP.NET offers complete syntax and processing compatibility with ASP applications. Developers simply need to change the file extensions from .asp to. aspx to migrate their files to the ASP.NET page framework. 16 Chapter 1 04235946 Ch01.F  12/11/02  11:43 AM  Page 16