Russia launches a full-scale military invasion of Ukraine, starting the largest war in Europe since the Second World War and displacing millions of people.
Queen Elizabeth II, the longest-reigning monarch in British history at over 70 years, dies at Balmoral Castle and is succeeded by Charles III.
OpenAI releases the chatbot ChatGPT, which quickly reaches hundreds of millions of users and drives a wave of generative artificial intelligence.
The James Webb Space Telescope, a NASA–ESA–CSA collaboration, is launched from French Guiana to observe the early universe in infrared.
The United Kingdom becomes the first country to leave the European Union, after 47 years of membership.
The World Health Organization declares the COVID-19 outbreak a global pandemic.
The United Kingdom gives the first doses of the fully authorised Pfizer–BioNTech COVID-19 vaccine, beginning a global vaccination campaign.