Chemicals of plants origin are defined as phytochemicals. These are produced by plants to help them resist against bacteria, fungi, virus, insects and other pathogens. Phytochemicals are produced by primary or secondary metabolism. They are classified into cartenoids, flavonoids, phenolic acids and lignans. Flavonoids are further divided into flavones, flavonones, anthocyanin, and flavanols. Phytochemicals are found in colorful parts of plants, fruits, legumes and vegetables. They have been found to be effective in preventing cancer, diabetes and cardiovascular diseases. Some common examples of phytochemicals include vitamin A, vitamin C and dietary fiber. This book includes some of the vital pieces of work being conducted across the world, on various topics related to phytochemicals. The various studies that are constantly contributing towards advancing technologies and evolution of this field are examined in detail. This book is a vital tool for all researching or studying phytochemicals as it gives incredible insights into emerging trends and concepts.