1) In Hindu mythology, the Bhagavad Gita is a sacred text that contains a conversation between Prince Arjuna and the god Krishna, who serves as his charioteer. It delves into philosophical and moral dilemmas and provides guidance on duty, righteousness, and the path to spiritual enlightenment.

2) The concept of self-driving cars, or autonomous vehicles, is being actively developed by companies such as Tesla, Google (Waymo), and Uber.

3) 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.

4) The universe is estimated to be around 13.8 billion years old.