Amaretto is a generally sweet liqueur originating from Italy from the mid-16th century. It is made from a base of almonds or apricot pits, and the name implies "bitter" in Italian, as a slight bitterness is imparted by the kernels used in the cooking.
It is often drunk "neat" or on the rocks, and is used in several official International Bartender's Association cocktails.
Disaronno Originale is a bittersweet almond flavored amaretto. Disaronno claims it's recipe is unchanged since 1525. It is produced in Saronno, a municipality of Lombardy, Italy.
The company has described Disarrono Originale as an infusion of apricot kernel oil with alcohol, burnt sugar, and the pure essence of seventeen selected herbs and fruits. The product apparently does not contain any almonds or other nuts.
The Disaronno bottle is a distinctive squarish decanter type bottle.
Luxardo is an Italian made Amaretto made from almonds picked in Sicily, and unlike other amarettos, Luxardo claims to use no additives like peach pits. It's aged for at least eight months in larch vats and is noted for it's smoothness and hints of vanilla.