Where to download opengl sdk (v. 3 or v. 4)?

Question

Wikipedia says that OpenGl V4.x is the latest. However my Visual Studio 2012 just offers the following version

#define GL_VERSION_1_1                    1

So my questions:

Which version is the most common that I should use? E.g. version 2.x because there are many tutorials, it is backward compatible etc.? I may have to mention that I normally prefer to write in C++, so is any version of Opengl e.g. offering namespaces? Are there huge differences between OpenGl 2,3 and 4?

And where can I get the Libs+Header files e.g. for OpenGl 4?

Answer 1

And where can I get the Libs+Header files e.g. for OpenGl 4?

You don't. OpenGL uses the so called "extension mechanism" to load functionality that's beyond the system ABI version. There exist third party libraries that do the extension loading and provide a header with the extended functionality.

Most popular is GLEW, which has its homepage at http://glew.sourceforge.net ; be warned though that right now of writing this GLEW is not up to date with OpenGL-3 and later core profiles. You must use compatibility profiles with GLEW or things get unstable.