this code is not working

Question

I get an error
'getElementById' is not defined
Line: 8
in this code
var button = getElementById('button');
var count = 0;
while (true){
if (button.val === true){
count += 1;
}
counter.innerHTML = count;
}
var counter = getElementById('counter');

Answer 1

document.getElementById()
not::
getElementById

Answer 2

"document" is missing!!
it should be
document. getElementById("button").