Introduction

Abstract

Perhaps humans always have been envious of the power, speed and beauty of certain animals. By taking their names and wearing their skin people thought they would acquire the same performances. It is only by our intelligence that we were able to survive in the animal world. By creating tools we were able to compensate our weak power and became the most dominant species of the world. The machines that have been built surpass in many ways the possibilities of animals. Airplanes are faster than most of the birds; submarines can dive deeper than whales. Our cars are faster than cheetahs.