There's no definitive answer to this question since everyone's perspective may be different. However, some popular contenders for the best subject in the world include mathematics, science, history and English. These subjects are often considered to be the most important and essential in providing a well-rounded education. They also tend to be the most challenging, which can make them more rewarding to study. Ultimately, the best subject is the one that interests and excites you the most - the one that you'll be passionate about learning more about.