Brief instructions on how to install C# on Windows

C# comes with the .Net framework.  Make sure you've installed .Net 2.0
or later version.  (.Net 1.1 is not enough).  It comes with Vista but
must be downloaded for XP.  One place you can get it from is
msdn2.microsoft.com/en-us/netframework/aa731542.aspx

Once installed, find the folder that contains the file csc.exe, which is
the C# compiler.  This is going to be something like
C:\Windows\Microsoft.Net\Framework\v2.0.50727\

(even if you installed .Net 3.5, there'll still be a v2.0* folder)

Now go to control panel - system - advanced - environment variables.

Edit the system variable PATH to include the above directory.  The directories
are separated by ;

Now you can write a C# program using some editor, go to the command
line prompt and type csc program.cs to complie program.  You'll get a
program.exe if compilation is successful which you can then run
directly: type program.exe or .\program.exe


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These instructions are approximate - they may differ a little depend on your
windows version.  You should be able to figure things out yourself from here.

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Alternatively, you can also download Visual C# Express, which is an IDE, for
free from microsoft.