Toggle the visibility of all matched elements by adjusting their height and firing an optional callback after completion. Only the height is adjusted for this animation, causing all matched elements to be hidden in a "sliding" manner. slideDown(String|Number,Function) slideUp(String|Number,Function) (optional) A string representing one of the three predefined speeds ("slow", "normal", or "fast") or the number of milliseconds to run the animation (e.g. 1000). (optional) A function to be executed whenever the animation completes. $("p").slideToggle("slow"); $("p").slideToggle("slow",function(){ alert("Animation Done."); });