What is the variable loadingbar responsible for in this code?

Question

JavaScript

In one of the articles such code is given. Simulates loading content when scrolling the page. In principle, everything is clear. Explain the purpose of the #loadingbar variable whose display property is being changed?

var loading = false;
$(window).scroll(function(){
  if((($(window).scrollTop()+$(window).height())+250)>=$(document).height()){
    if(loading == false){
      loading = true;
      $('#loadingbar').css("display","block");
      $.get("load.php?start="+$('#loaded_max').val(), function(loaded){
        $('body').append(loaded);
        $('#loaded_max').val(parseInt($('#loaded_max').val())+50);
        $('#loadingbar').css("display","none");
        loading = false;
      });
    }
  }
});

$(document).ready(function() {
  $('#loaded_max').val(50);
});

Answer 1

#loadingbar is not a variable, it's an element on the page that actually displays the loading progress.
- scrolled
- the bar was displayed
- loading of data began
- upon completion, the bar was hidden