Edit in JSFiddle

//Variable scope example for programadorobjetivo.co
function externa() {

    var list = document.getElementById("list");
    
    for (var i = 1; i <= 5; i++) {
      var item = document.createElement("button");
      item.appendChild(document.createTextNode("Click me " + i));
    
      var j = i;
      item.onclick = function interna (event) {
        alert("Item " + j + " is clicked.");
      };
      list.appendChild(item);
    }
    
};

externa();