C# is a general-purpose, object-oriented programming language intended to be simple and modern. It uses ; and {} similarly to C++ and Java. A basic C# program structure includes namespaces, classes, methods, attributes, and a main method. It supports common data types like integers, floats, booleans, and objects. C# code is compiled to the Common Language Runtime. Key advantages over C++ and Java include more legible code through formalized get/set methods and cleaner event management using delegates.