Lecithin is a complex, naturally-occurring mixture of phospholipids that most often comes from soybean oil. Phospholipids are a part of almost all biological membranes. Phospholipids are the surface-active portion of lecithin, the part that gives lecithin most of its functional properties.
A "Phospholipid" is one of Nature's emulsifiers providing a variety of surface-active properties to two different substances like oil and water, allowing them to blend together easily. This characteristic of blending different substances makes lecithin an invaluable low-cost, functional ingredient in foods, nutritional products, many industrial applications and in animal feeds, too.
Lecithin and its primary component, choline, are also believed to play important roles in cardiovascular health; liver and cell function; fertility, pregnancy and child development; and possibly memory.
Many different grades of lecithin are available for business and consumer use. Lecithin granules (3rd bottle from the right) and liquids are dietary supplements found in health food stores everywhere!
The word "Lecithin" is derived from the Greek lekithos meaning yolk of an egg. The principal phospholipids are PC (phosphatidyl-choline), PE (phosphatidyl-ethanolamine), and PI (phosphatdyl-inositol). If you just refer to them as PC, PE and PI, you will be in the company of many other tongue-tied people!