Most of the ones we use come from seeds. The use of seed oils is ancient. In contrast to essential oils, these are made up of glycerides and are not volatile.
Glycerides contain fatty acids and glycerol.
The structures of the fatty acids determine many of the properties of the oils and fats. They are the food reserve of the germinating embryo. Similar oils and fats are obtained from animals. In general, the longer the chains of the fatty acids the higher boiling the oils or fats are. Peanut oil has lots of C 20 fatty acids and is high boiling.