From Wikipedia:

Similar to the year 2020, 2021 was also heavily defined by the COVID-19 pandemic, due to the emergence of multiple COVID-19 variants. The major global rollout of COVID-19 vaccines, which began at the end of 2020, continued in 2021. Most major events scheduled for 2020 that were postponed due to the pandemic were hosted in 2021, including the 26th United Nations Climate Change Conference, Expo 2020, and sporting events such as UEFA Euro 2020, the 2020 Summer Olympics and Paralympics, as well as the 2021 Copa América.[1]

2021 additionally witnessed the rise of non-fungible tokens as a part of the global economy[2] and numerous advancements in space exploration, particularly by the United Arab Emirates, NASA and SpaceX, including the launch of the James Webb Space Telescope. Civil unrest grew in 2021, with coups occurring in Sudan, Myanmar, Mali and Guinea, and insurrections occurring in Armenia and the United States.