event.which
For key or mouse events, this property indicates the specific key or button that was pressed.
Category: Version 1.1.3
jQuery.browser
Contains flags for the useragent, read from navigator.userAgent. This property was removed in jQuery 1.9 and is available only through the jQuery.migrate plugin. Please try to use feature detection instead.
jQuery.unique()
Sorts an array of DOM elements, in place, with the duplicates removed. Note that this only works on arrays of DOM elements, not strings or numbers.