JAVA

Bonjour,
Merci de m'expliquer ces lignes du langage JAVA
function CheckAnswer(){

var i = 0;
var TotalCorrect = 0;
var x = 0;
var Score = 0;

for (i=0; i<CorrectAnswers.length; i++){
if (document. questionnaire.elements[i*2].selectedIndex == CorrectAnswers[i]){
document. questionnaire.elements[(i*2)+1].value = rightchar;
TotalCorrect++;
}
else{
document.QuizForm.elements[(i*2)+1].value = wrongchar;
}
}
Score = Math.floor((TotalCorrect*100)/CorrectAnswers.length);
document.CheckForm.ScoreBox.value = Score + '%';
}