Windows Update: .NET Framework, should I install?

Factual Questions
1

I use windows XP. For probably a year or so there has been an update on the windows update website called Microsoft .NET Framework version 1.1. I am curious what this update does and why anyone needs it.
I noticed that in the “read more…” it gives a wonderful informative description that “Windows users need to install the .NET Framework to run applications developed using the .NET Framework." That’s wonderful, I am overjoyed. What does this mean?
I have never run into problems not having this and it seems that if it is installed it will just be one more thing that will never be useful and will only make my machine run slower (not to mention it is a 20 meg download).

So, what’s the straight dope on this? Should I install it or not?

2

To put it most simply, there are some application that require it.

If you don’t have it, they won’t run.

If all your progs run, you don’t need it. And I hope programs that need it make themselves clear that they need it.

3

Microsoft’s new development environment, Visual Studio.NET, uses a common set of routines, so that whether a program is written in Visual Basic, C++, C#, or any of the other .NET languages, the compiled source will be the same. In order for programs written in .NET to run on your computer, you need to have the .NET Framework installed. If this is a commercial program, you can be sure that the Install program will check for the Framework and install it if it’s not present. If you or someone you know is an amateur programmer and you want to run the program on your computer, you will need to install it.

4

Just to clarify a bit on what Fat Bald Guy said, you can still make non-.NET apps with Visual Studio .NET, as I did in the prog described in this thread.