Need a explanation on what are these code for.

function getScore(form) {
var score = 0;
var currElt;
var currSelection;
for (i=0; i<numQues; i++) {
currElt = i*numChoi;
for (j=0; j<numChoi; j++) {
currSelection = form.elements[currElt + j];
if (currSelection.checked) {
if (currSelection.value == answers) {
score++;
break;
}
}
}
}

score = Math.round(score/numQues*100); // math.round function will return the whole number to the nearest specified value for example 1.9 will show as 2
form.percentage.value = score + "%"; // The score will be displayed in percentage

var correctAnswers = "";
for (i=1; i<=numQues; i++) {
correctAnswers += i + ". " + answers[i-1] + "\r\n";
}
form.solutions.value = correctAnswers;
}