Here is a great confidence giver. It is a Scrap of intimate material which can plunge us into despair or make the day for us. Can you count the number of times you have felt elated because your hair has changed the mood? The change need not be dramatic - a comb, a ribbon or a new-fangled plait can give a fresh twist to your hair and a lift to your spirits in seconds. A change of hairdresser can sometimes make all the difference to the way you see yourself and a new hairstyle if it's the best of all morale-boosters. Hair in top condition is marvelous stuff, and the word stuff is just right. For although it is a part of your body, hair behaves like an adaptable, amenable and very beautiful material. Together with the nails, it is the one part of the body you can touch without sensation, which is surely why it is so abused. The health of your hair goes up and down with your general health, and as the food you eat has everything to do with the well-being of your hair and scalp, these are often the first parts of you to show signs of strain when you have been ill or are dieting. Hair also behaves differently according to climate and age. Your hair is the most changeable part of your appearance and for something like six thousand years has been regarded as a high fashion accessory. As with clothes, fashion in hairstyles reflect the state of society. The hey-day of the elaborate coiffure was in the reign of Elizabeth I when there were unlimited time and money in court. Conversely, hairstyles were reduced to their simplest during the two world wars.