1) The most-watched TV series finale in the United States was "MAS*H," with an estimated 105 million viewers.

2) The development of blockchain technology, first introduced in 2008 with the creation of Bitcoin, has enabled secure and decentralized digital transactions and led to the emergence of cryptocurrencies.

3) The Black Lives Matter movement gained renewed momentum in 2020 following the killings of George Floyd, Breonna Taylor, and others, sparking protests and discussions on systemic racism, police reform, and social justice around the world.

4) The Sahara Desert, located in North Africa, is the largest hot desert in the world, covering an area of about 9.2 million square kilometers (3.6 million square miles). It is characterized by vast stretches of sand dunes, rocky plateaus, and extreme temperatures.