1) The world's first paper money was created in China over 1,000 years ago.

2) In Norse mythology, Valhalla is a majestic hall located in Asgard, the realm of the gods. It is the afterlife destination for brave warriors who die in battle, where they are greeted by the Valkyries and engage in feasting, drinking, and preparing for the final battle of Ragnarok.

3) The first successful mass-produced personal computer, the IBM PC, was introduced in 1981 and played a significant role in popularizing the use of computers in homes and offices.

4) 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.