1) The Age of Exploration, during the 15th and 16th centuries, saw European explorers such as Christopher Columbus and Vasco da Gama reach new lands and establish trade routes.

2) The Sahara Desert, located in North Africa, is the largest hot desert in the world, covering an area of about 9.2 million square kilometers (3.6 million square miles). It is characterized by vast stretches of sand dunes, rocky plateaus, and extreme temperatures.

3) Hindu mythology, deeply rooted in Indian culture, revolves around a pantheon of gods and goddesses, including Brahma, Vishnu, Shiva, Saraswati, and Lakshmi. These deities represent various aspects of existence and play important roles in Hindu religious traditions and epics like the Mahabharata and Ramayana.

4) The American Civil Rights Movement, led by figures like Martin Luther King Jr., fought for equal rights and helped bring about significant social and legislative changes.