Shortbread is a type of cookie which is traditionally made from one part white sugar, two parts butter, and three parts plain white flour, although other ingredients like ground rice or cornstarch are sometimes added to alter the texture. Shortbread is so named because of its crumbly texture (from an old meaning of the word short). The cause of this texture is its high fat content, provided by the butter. The related word "shortening" refers to any fat that may be added to produce a short (crumbly) texture. 
- Preheat the oven to 140ºC (275ºF or Gas Mark 1).
- Cream the butter with the sugar until light and fluffy.
- Sift the flour and salt into the mixture and work into the fat and sugar until completely amalgamated.
- Shape the dough into a ball and roll out to about 1.3 cm (½ inch) thick.
- Cut into squares or rectangles and prick the tops with a fork in two parallel lines.
- Bake in the oven for 30 to 40 minutes or until the shortbread is lightly browned.
- Leave them on a cooling rack to cool.
- Store in a cool place in an airtight container.
- "Online Etymology Dictionary". http://www.etymonline.com/index.php?term=shortening. Retrieved 2007-01-25.