ASP.NET introduces two major features: Web Forms and Web Services

Web Forms

Developers not familiar with Web development can spend a great deal of time, for example, figuring out how to validate the e-mail address on a form. You can validate the information on a form by using a client-side script or a server-side script. Deciding which kind of script to use is complicated by the fact that each approach has its benefits and drawbacks, some of which aren't apparent unless you've done substantial design work. If you validate the form on the client by using client-side JScript code, you need to take into consideration the browser that your users may use to access the form. Not all browsers expose exactly the same representation of the document to programmatic interfaces. If you validate the form on the server, you need to be aware of the load that users might place on the server. The server has to validate the data and send the result back to the client. Web Forms simplify Web development to the point that it becomes as easy as dragging and dropping controls onto a designer (the surface that you use to edit a page) to design interactive Web applications that span from client to server.

Web Services

A Web service is an application that exposes a programmatic interface through standard access methods. Web Services are designed to be used by other applications and components and are not intended to be useful directly to human end users. Web Services make it easy to build applications that integrate features from remote sources. For example, you can write a Web Service that provides weather information for subscribers of your service instead of having subscribers link to a page or parse through a file they download from your site. Clients can simply call a method on your Web Service as if they are calling a method on a component installed on their system — and have the weather information available in an easy-to-use format that they can integrate into their own applications or Web sites with no trouble.

Windows Forms

Windows Forms is the name of a unified set of classes that provides support for creating traditional desktop applications — applications that have a graphical user interface (GUI). Windows Forms make it easy to develop end-user applications using any .NET programming language. Furthermore, through Visual Studio .NET, developers can easily design forms by using drag-and-drop editing.

Visual Studio .NET

Visual Studio .NET fulfills the promise of a single development environment for all languages. Visual Studio .NET simplifies development in a mixed-language environment through features such as support for end-to-end debugging across all programming languages; visual designers for XML, HTML, data, and server-side code; and full IntelliSense support.

Visual Studio .NET is able to provide this level of integration because it relies and builds on the facilities of the .NET Framework. Designers for Web forms and Windows Forms enhance developer productivity during the development cycle. Integration of deployment features enhances productivity during post-deployment debugging.

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