1) The ancient city of Pompeii was preserved under layers of volcanic ash after the eruption of Mount Vesuvius in 79 AD, providing valuable insights into Roman life.

2) Leonardo DiCaprio is an acclaimed American actor and environmental activist. He has starred in numerous successful films, including "Titanic," "The Revenant," and "The Wolf of Wall Street," and has been recognized with several awards, including an Academy Award.

3) The Internet of Things (IoT) refers to the network of physical devices, vehicles, appliances, and other objects embedded with sensors, software, and connectivity.

4) The first commercial mobile phone, the Motorola DynaTAC 8000X, was released in 1983 and weighed nearly 2 pounds.