Every couple of years, Microsoft Corp. hoists a flag to rally the troops. Win32, OLE, Component Object Model (COM), ActiveX and Windows DNA would, we were told, revolutionize the business of creating and deploying software. Because these campaigns addressed important issues, they were greeted with a measure of enthusiasm. Because they entailed risk, uncertainty and retraining, they were greeted with an equal measure of weary skepticism.

So it is for the new campaign, which is called .Net. But this time, enthusiasts appear to outweigh skeptics. Everyone agrees that business applications and network services are becoming the same thing. IT has learned, and will never forget, the lessons of the first-generation Web: open standards, universal access, rapid development, continuous deployment.

Now the second-generation Web is being constructed, and Microsoft is determined to be one of its architects. Chastened by its failure to catch the first wave and challenged by the thriving open-source and Java communities, it's put together a compelling strategy. It aims, as usual, to deliver tools and environments that take care of plumbing so the majority of developers can focus on creating the applications they're hired to build. Here's a blueprint for the second-generation Web from a .Net perspective:

XML

.Net uses XML for universal representation, exchange and storage of all kinds of data -- and, in particular, to describe and manipulate component interfaces.

Components

Today, components come in many flavors: shared libraries, script language modules and application-specific plug-ins. Component models like COM and Common Object Request Broker Architecture (CORBA) make code reuse among these flavors possible but not easy, so it often doesn't happen. .Net aims to make component construction and reuse so easy that there's no excuse not to do it.

Objects

In theory, objects created by object-oriented programming (OOP) languages are components. In practice, the languages' object models don't match cross-language component models like COM and CORBA. The .Net Common Language Runtime, a universal OOP engine, aims to solve this problem.

Because all .Net languages share the same object model, an object written in any language is automatically a component available to all others.

A bonus: OOP-style inheritance works across component and language boundaries.

Frameworks

Every programming language comes with standard libraries -- called frameworks in the case of OOP languages -- that encapsulate common code and define patterns for using it. The Java Development Kit's class libraries are such a framework. The .Net framework covers similar ground but in a language-neutral way. C#, Visual Basic.Net and other .Net languages are only lenses through which programmers see the same underlying framework.

Glue

In every programming environment, there's a division of labor. A few people make the components that many others glue together. Components are often written in compiled languages such as C and C++. The glue is usually a scripting language, ideally one supported by an integrated development environment. The first-generation Web is bound together by glue languages: JavaScript, Perl, Python, PHP and several forms of Visual Basic. But it's also balkanized into glue-language communities. One .Net goal is to universalize the glue -- making components, plus the knowledge and the

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