Shortening is a term that covers fats that are solid at room temperature and is ideal for creating 'short' types of pastries, biscuits, desserts and cakes (as opposed to 'long' stretchy breads, pastas, pizza doughs etc). Vegetable shortening is often used as a substitute for butter in baking and suits vegans and dairy intolerant diets and the hot temperatures of Australia for cake icings/buttercream.
Shortening contains 100% fat, meaning there is no water in it, unlike butter. In baking, no steam will be produced with shortening, but it will be with butter, which creates a slightly different effect. Cookies baked with shortening will likely be more tender and softer than those made with butter. Shortening is rather flavourless, therefore additional flavours like essence are often added. For a flaky or crumbly dessert, shortening is probably your answer, and your family will thank you for those baked goods as soon as they get a taste!