What does the + sign in front of a function name mean in JavaScript?

Which is not a valid Date Object method in JavaScript?

Which event can be used to validate the value in a field as soon as the user moves out of the field by pressing the tab key?

Is the following statement regarding expression closures in JavaScript true or false? The syntax function(x) {return x*x;} can be written as function(x) x*x.

How can the user's previously navigated page be determined using JavaScript?

Which statement regarding this String prototype is correct? String.prototype.doSomething = function(suffix) { return this.indexOf(suffix, this.length - suffix.length) !== -1; };

Result of C given code? var a = '1'; b = 2 * a; c = typeof(b);

which is correct in order to send a HTML form post request using XMLHttpRequest?

What does the following statement do? document.title = 'JavaScript';

Consider the following JavaScript alert: You want the user to see the above message upon opening the page. How will you implement this?

You've embedded the document.write() method to write some text within a pair of table tags. Upon loading the file, however, you get some garbled junk on the page where that text should be. What could be the reason for this?