What is C# and .NET

C# is an elegant and type-safe object-oriented programming language that enables developer to build a variety of secure and robust applications on the top of .NET Framework. It was developed by the team which was led by Anders Hejlsberg. C# was first appeared on 2000 AD.

Hello World program in C#

using System;

namespace HelloWorld
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Hello World!");
        }
    }
}

Differences between C# and .NET

C# is a general purpose object-oriented programming language like Java, C++ etc which runs on the .NET Framework. Where as .NET is a blanket term that tends to cover both the .NET Framework(an application framework library) and the Common Language Runtime which is the runtime in which .NET assemblies run.

Remember: .NET isn't just a library, but also a runtime for executing applications.

i.e. .NET Framework includes a large class library named Framework Class Library (FCL) and provides user interface, data access, database connectivity, cryptography, web application development, numeric algorithms and network communications.

References

What is the difference between C# and .NET?