What is important that makes C# the first games maker in the world ?
The game engine 'Unity' is based on C#. Also Unity is free and easy to use. Check this link for more information. https://www.sololearn.com/Discuss/708938/?ref=app
When C# compared with Java ?
C++ came before C# C# uses some of the principles from the C++ but is easier to learn. C# can be used to build games for the popular Unity engine, though Unity has C++ at its core. The Unity engine functions on most platforms, so games built in C# have cross-platform functionality thus making it the go to source for game development.