1) Banks provide various financial products, including savings accounts, checking accounts, credit cards, mortgages, and investment services.

2) The world's largest diamond, the Cullinan, was discovered in South Africa in 1905 and weighed over 3,000 carats.

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

4) The smallest unit of time is known as a zeptosecond, which is equal to one trillionth of one billionth of a second.