one day I've got a question, "In general CSharp program, it should have the main function, which is a start point of the program. So, where is the main function of Unity project ?" I search for several hours to find the answers, and got some info below: - Unity engine is written by CPP, not the CSharp - CSharp script is just a method to use Unity engine through API - we cannot usually access on deep side of Unity engine (especially referenced https://answers.unity.com/questions/9675/is-unity-engine-written-in-monoc-or-c.html) so I understood as "Actual main function is written by CPP and invisible" then, I have new 2 questions below: #1. there is no way to learn about how Unity runs ? like https://docs.unity3d.com/Manual/ExecutionOrder.html #2. how the CSharp script can execute CPP code (Unity engine) ? I heard dotnet makes it possible, but I cannot find an explanation for it sorry for bad english, I'll really appreciate for your answer !