When using an Apple system the OpenGL library is maintained by Apple themselves and under Linux there exists a combination of graphic suppliers' versions and hobbyists' adaptations of these libraries. This also means that whenever OpenGL is showing weird behavior that it shouldn't, this is most likely the fault of the graphics cards manufacturers (or whoever developed/maintained the library).

Since most implementations are built by graphics card manufacturers. Whenever there is a bug in the implementation this is usually solved by updating your video card drivers those drivers include the newest versions of OpenGL that your card supports. This is one of the reasons why it's always advised to occasionally update your graphic drivers. Khronos publicly hosts all specification documents for all the OpenGL versions. The interested reader can find the OpenGL specification of version 3.3 (which is what we'll be using) here which is a good read if you want to delve into the details of OpenGL (note how they mostly just describe results and not implementations). The specifications also provide a great reference for finding the exact workings of its functions. In the old days, using OpenGL meant developing in immediate mode (often referred to as the fixed function pipeline) which was an easy-to-use method for drawing graphics. Most of the functionality of OpenGL was hidden in the library and developers did not have much freedom at how OpenGL does its calculations. Developers eventually got hungry for more flexibility and over time the specifications became more flexible developers gained more control over their graphics. The immediate mode is really easy to use and understand, but it is also extremely inefficient. For that reason the specification started to deprecate immediate mode functionality from version 3.2 and started motivating developers to develop in OpenGL's core-profile mode which is a division of OpenGL's specification that removed all old deprecated functionality. When using OpenGL's core-profile, OpenGL forces us to use modern practices. Whenever we try to use one of OpenGL's deprecated functions, OpenGL raises an error and stops drawing.

The advantage of learning the modern approach is that it is very flexible and efficient, but unfortunately is also more difficult to learn. The immediate mode abstracted quite a lot from the actual operations OpenGL performed and while it was easy to learn, it was hard to grasp how OpenGL actually operates.

Opengl 3.3 graphics card