the programmer write different code for each version of Windows. The Runtime handles those complexities and allows software developers to focus on the functionality of their application instead. In theory, the Runtime could be ported to other operating systems such as Linux so that an application you create for Windows will run on Macs or Linux machines. This is what Java attempted to do with their virtual machine, which .NET was heavily influenced by. When your programs run, they run "inside" or are controlled by the .NET Runtime. When an end- user clicks an icon to open your program on their computer, the first thing your program will automatically do is “ask” the .NET Runtime to “host” it. Therefore, any computer you want to use your application on must have the .NET Framework installed or else it will not work on that computer. We do not cover how to distribute your application in the BEGIN01 series, however there are other videos on LearnVisualStudio.NET that cover this topic (see video “3550 - Introduction to Deploying .NET Apps” for more information.)
.NET Framework Class Library – also known as the “FCL”. This is what you will become intimately familiar with. It contains hundreds of classes, each with dozens of properties and methods that allow you to do almost anything you would want to within your program. You won't get very far without using the Class Library -- database access, sending emails, accessing files on a hard drive, creating dynamic web pages -- everything you want to do is made possible through this set of code that you reference within your applications.
.NET Language Compilers - These are a set of programs that take the source code you write in a particular language (such as Visual Basic.NET, C#, J# or managed C++), and compile them into the Microsoft Intermediate Language (MSIL, or just IL) which is then run by the .NET Runtime. The compiler for Visual Basic.NET is vb.exe. Each programming language has its own compiler that knows how to interpret source code you write into MSIL and store that MSIL in an Assembly file. The compiler also alerts you to problems compilation errors in your code due to mistakes in typing, incorrect logic, etc.
Other utilities - There are over a dozen other tools that come with the .NET Framework for various purposes. Many of these you may never need, and some are used behind the scenes by Visual Studio.NET.
There are MANY other features of .NET, such as a common type system that allows cross-language interoperability, the inner workings of Assemblies (what your application gets compiled into), application domains for isolation of applications and their processes, and many complex topics. If you want to really dig in
Supplemental Readings for the Express Edition Videos Copyright © 2005 LearnVisualStudio.NET