You'll find a staggering amount of classes and methods inside the Microsoft .NET Framework. To organize the classes, they are placed within groups called namespaces. A namespace is simply a logical division, and can be as large or small as desired.
Any Microsoft .NET developer should become familiar with a free sample application from Microsoft called the .NET Framework Class Browser (see Figure 1.1), available online at http://www.IntensitySoftware.com/ClassBrowser. However, the class browser is part of the QuickStart tutorials published by Microsoft and should be available on any machine with the QuickStart tutorials installed. If you accepted defaults during the installations of the QuickStart examples, it should be installed locally at http://localhost/quickstart/aspplus/samples/classbrowser/vb/classbrowser.aspx. Much more than a set of static help pages, the class browser loads the namespaces at runtime to display their methods and properties. Thus, if you are running the class browser locally, you are assured of up-to-date information on the assemblies installed on your system.
Figure 1.1. The Microsoft .NET Framework Class Browser application is used to browse the framework's built-in classes and methods.
The class browser shows you the list of Microsoft .NET Framework namespaces on the left side of your screen as seen in Figure 1.1. It is absolutely worth your time to become familiar with these namespaces and the classes they contain.