Why do people enjoy these challenges? There are probably many reasons. One is curiosity. The other is the personal feeling of success, of achievement, and nowadays, for some people, it is a business.
Today, we still have many challengers before us. Medical science faces the challenges of conquering many diseases which still attack human beings. Engineers and planners must build new cities, design and produce new kinds of transportation. Scientists must develop new forms of energy. In short, we live in an age of challenges.