Silver has the highest electrical conductivity of all elements, making it ideal for electronics, though copper is more widely used.

Brahmagupta (7th century) formalized the rules for zero and negative numbers, laying the foundation of modern mathematics.

The Ming dynasty expanded and fortified the Great Wall between the 14th–17th centuries, much of which still stands today.

Kantian ethics emphasizes duty and moral laws derived from reason, proposing actions are right if based on universal principles.

William Harvey in 1628 demonstrated that blood circulates continuously through the body, powered by the heart, revolutionizing medicine.