1) Robert Downey Jr. is an American actor known for his portrayal of Iron Man in the Marvel Cinematic Universe. He has also starred in films such as "Sherlock Holmes," "Chaplin," and "Tropic Thunder," and has received critical acclaim and commercial success for his performances.

2) The United Nations (UN) is an international organization founded in 1945 with the goal of promoting peace, security, and cooperation among nations through diplomatic and political means.

3) The concept of reinsurance, which is insurance for insurance companies, originated in the 17th century.

4) Cricket, originating in England, is a popular sport played in many countries and is known for its distinctive rules and terminology.