A pistachio is the seed of a tree native to the mountainous regions of northern Iran, Afghanistan and Turkey -- and pistachios figure heavily in the cuisines of these cultures.

Even though it's not a true nut, the pistachio is considered a culinary nut and has been used for thousands of years in both sweet and savory dishes.

Pistachios are similar in texture to almonds, with a more complex, floral flavor and a pale green color.