What is the main difference between C++ vs C++.NET? [duplicate]

Answer 1

Managed C++ is a now deprecated Microsoft set of deviations from C++, including grammatical and syntactic extensions, keywords and attributes, to bring the C++ syntax and language to the .NET Framework. These extensions allowed C++ code to be targeted to the Common Language Runtime (CLR) in the form of managed code as well as continue to interoperate with native code. Managed C++ was not a complete standalone, or full-fledged programming language.

Managed C++

#using 
using namespace System;

int main()  {
  Console::WriteLine("Hello, world!");
  return 0;
}

Vanilla C++

#include 
using namespace std;

int main()
{
  cout << "Hello, world!";
 return 0;
}