Moved to software
Topic title edited.
It appears that u are a newbie programmer or new to microsoft programming world. Visual basic.net is a programming language by Microsoft. Now it is called Visual Basic 2005 in its newer version. Visual Basic 2005 Express Edition is an IDE i.e. Integreted Development environment which u can use to develop programs in Visual Basic 2005 programming language.
This is language can be a starting point to develop certain programming concepts needed for a newbie. Download and install VB 2005 express edition on ur pc and start learning. There are free video tutorials available at Microsoft website. Download them too. They are REALLY good.
I'm pretty sure that the name is Edition (version), not addition (adding)
A while ago, there was a language called BASIC. It stood for Beginner's All-purpose Symbolic Instruction Code. It was a simplistic and easy to use programming language. Around 1997 or so, Microsoft created Visual Basic. It was essentially the same as BASIC. However, it allowed users to visually click and drag parts of the user interface. Now, Visual Basic is packaged with Microsoft Visual Studio, a software suite which includes several "visual" languages, such as Visual Basic and Visual C++. Recently, Microsoft released Visual Studio Express Edition for free. This is a version for amateur programmers who would not want to pay hundreds of dollars for the full version. Visual Basic Express Edition is a part of Visual Studio Express Edition.
Sorry if that was too hard to understand, I tried to make it simple.
I have both, i've started Visual Basic Express Addition, later i moved to Visual Studio.