Terpenoids represent the largest and most widely distributed class of natural, high-value chemicals, comprising more than 55,000 distinct molecules. Besides the wide range of biological properties, these natural compounds have found significant commercial value as pharmaceuticals, flavours and fragrances, commodity chemicals, and, more recently, as potential biofuels. Squalene is a natural lipid belonging to the terpenoid family and a precursor of cholesterol biosynthesis. Squalene has attracted increasing attention during the past few years due to their biological activities and natural abundance and is potential targets for the food and pharmaceutical industries. This book discusses the molecular properties, applications, functions and health implications of terpenoids and squalene.