How to learn OpenGL correctly?

Question

OpenGL

The question arose due to differences between versions,
I read that the new OpenGL is too different from the old ones.
I don’t know what this difference is, well, I just realized that you can write your own code for some stages of the graphics pipeline.
So is it better for a beginner to immediately look for information on the new OpenGL, or first learn the basics of the old one?
How different are they?
PS: Can you tell me what advantages this gives me as a beginner in OpenGL? What are the most important differences?

Answer 1

I, too, just started (purely as a hobby) trying to join the OGL and decided for myself (properly, this is clearly written on the chronos website) that in 2020 it makes no sense to study 2.x - only 3.0 and higher. Actually, it would be desirable 3.2 and higher, but I have, for example, a relatively old laptop (however, it can cope with everyday tasks quite well: four 2.5GHz threads, 8GB of RAM), which only supports OpenGL 3.0 - and I'm not focused on "games" , but all sorts of semi-engineering software (where not "beauty" is important, but simply dynamic rendering of complex models with plain textures, or no textures at all), so I chose 3.0 as the "beginning" for myself.
Here is a piece about the fundamental difference between versions 2. x and 3.x: https://www.khronos.org/opengl/wiki/OpenGL_Context...
Here this guy has a cool series about OGL on Habré: https://habr.com/ru/users/haqreu/posts/ - he says a smart idea there: first, figure out how 3G graphics are rendered (using the example of a soft render - there is a separate course of articles on it) and then transfer this knowledge to iron