Programming language developed by
Microsoft whose syntax is very similar to C++, is completely object-oriented and allows fast development.
Contrary to what many believe, C# is NOT proprietary...
Java is actually proprietary. However, because
Microsoft still dominates its direction, it may be considered to be "semi-de facto" proprietary at this stage.
C# traded off some runtime speed for safety and quick development. More optimized compilers in the near future may reduce this speed disadvantage while retaining the advantages.
Holistically, C# is perhaps the best programming language in existence.