1) Democracy is a system of government in which power is vested in the people, who exercise it through elected representatives. It allows for political participation, freedom of speech, and protection of individual rights and liberties.

2) The term "bull market" refers to a period of rising stock prices, while a "bear market" refers to a period of falling stock prices.

3) The highest-grossing concert tour of all time is U2's "360° Tour," which earned over $735 million in ticket sales.

4) Priyanka Chopra Jonas is an Indian actress, singer, and film producer who has made significant contributions to both Bollywood and Hollywood. She gained international fame through her role in the television series "Quantico" and has since starred in successful films.