Can someone explain it to me what closure is in real simple language ? [duplicate]

Answer 1

I like the Google example for Javascript (you can morph it for C# easily). It's not something a 5 year old would understand but then I doubt an average 5 year old would understand what a function was.

/*
* When a function is defined in another function and it
*    has access to the outer function's context even after
*    the outer function returns
* An important concept to learn in Javascript
*/

function outerFunction(someNum) {
  var someString = 'Hai!';
  var content = document.getElementById('content');
  function innerFunction() {
    content.innerHTML = someNum + ': ' + someString;
    content = null; // IE memory leak for DOM reference
  }
  innerFunction();
}