$("p").addClass("selected")

Applies the "selected" class to all paragraphs

$("p").removeClass("selected")

Removes the effect of "selected" class to all paragraphs

$("p").addClass("special")

Applies the "selected" class to all paragraphs

$("p").removeClass("special")

Remove the effect of "selected" class to all paragraphs

$("p").attr("align", "left")

Aligns all paragraphs to the left

$("p").attr("align", "right")

Aligns all paragraphs to the right

$("p").removeAttr("align", "right")

Removes the align attribute from all paragraphs.

$("p").toggleClass("special")

Toggles the selected tag on and off.