American basketball player Kobe Bean Bryan became the youngest player to record 25,000 career points on January 21, 2010, when he was 31 years and 151 days old. He played shooting guard in the National Basketball Association for the Los Angeles Lakers for the entirety of his 20-year career (NBA).

Paul Gardner Allen, an American business mogul, computer programmer, researcher, investor, and philanthropist, was born on January 21, 1953. In 1975, he and his childhood friend Bill Gates co-founded Microsoft Corporation, which contributed to the microcomputer revolution of the 1970s and 1980s. Microsoft rose to become the leading provider of personal computer software.

James Gosling created Java, an Object-Oriented programming language, in the early 1990s. On January 23, 1996, the very first version was made available. Java 1 refers to the primary stable variant, JDK 1.0.2. This project was started by the team to create a language for digital gadgets like set-top boxes, televisions, etc.

On January 22, MIT alumni Timothy "TJ" Creamer SM '92 became the first astronaut to use a new Internet connection to tweet live from orbit. 

"Hello there, Twitterverse! We are currently tweeting LIVE from the International Space Station—the first live tweet from space! :) Send yours as soon as possible "Creamer's Twitter remark said it all. 

The message was made possible through the Crew Support Local Area Network, a novel technology that allows astronauts aboard the International Space Station (ISS) to connect to the Internet via existing communication channels.

She married Donald Trump, a real estate mogul and television celebrity, in 2005 and gave birth to their son Barron in 2006. She became a naturalised citizen of the United States later that year. She is the second naturalised woman, after Lousia Adams, to become first lady, as well as the first non-native English speaker.

Sir Donald George Bradman, also known as "The Don," was an Australian cricketer who represented his country internationally. He was largely regarded as the best batsman to have ever lived and lived from 27 August 1908 to 25 February 2001. On January 23, 1948, he made his 12th and final 200-mile crossing.

Subhas Chandra Bose, born on January 23, 1897, was an Indian nationalist whose uncompromising patriotism made him a hero in India, but whose attempts to free India from British domination with the support of Nazi Germany and Imperial Japan during World War II left a tumultuous legacy. Bose was originally given the title Netaji (Hindustani: "Respected Leader") by Indian troops of the Indische Legion and German and Indian authorities in Berlin's Special Bureau for India in early 1942. It is currently widely used in India.

Menon established the record for the longest speech before the United Nations Security Council (8 hours) in 1957, supporting India's claims to the disputed territory of Kashmir, garnering him great acclaim and the moniker "Hero of Kashmir."