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 musical "Les Misérables" is one of the longest-running shows in the West End and Broadway, with over 13,000 performances.

3) The invention of the transistor by Bell Laboratories in 1947 revolutionized electronics and paved the way for the development of smaller, more efficient electronic devices.

4) The Cuban Missile Crisis in 1962 brought the United States and the Soviet Union to the brink of nuclear war during the Cold War.