jQuery: Check Element Visibility

For a single element, it is very easy to check if an element is hidden or visible:

$(element).is(":visible");
$(element).is(":hidden");

To match all elements, use the ff:

$('element:hidden');
$('element:visible')

You can also check the CSS display property:

if ( $(selector).css('display') == 'none' ) { 
  // is hidden
} else {
  // is visible
}