Shortening is classified as a fat because it is solid at room temperature. Shortening can be made with animal or vegetable fats, or a combination of them. Those based on vegetable oil are made solid by hydrogenation. Read the label. If it says "pure vegetable shortening", the product is exactly that. The phrase "pure shortening" means that either animal or vegetable fats, or both, could have been used. If the word "pure" is missing, the manufacturer has included additives to lengthen the shortening's storage life or improve some of its cooking properties. Those additives, unfortunately, lower the smoking point when cooking.