Roger Federer is married to Miroslava Federer (née Vavrinec), a former Women's Tennis Association player whom he met while competing for Switzerland at the 2000 Sydney Olympics. Mirka, as she is more commonly known, retired from the tour in 2002 due to a foot injury. On 11 April 2009, they married at Wenkenhof Villa in Riehen, near Basel, in the presence of a small group of close friends and family. She gave birth to identical twin girls in 2009. In 2014, they welcomed another set of identical twins, this time boys.

Jyotirao Govindrao Phule was born on April 11, 1827, and died on November 28, 1890. He was a Maharashtra-born Indian social activist, thinker, anti-caste social reformer, and writer. His work included the abolition of untouchability and the caste system, as well as efforts to educate women and oppressed caste people. He and his wife, Savitribai Phule, were pioneers in Indian women's education. In 1848, Phule established his first girls' school in Pune, at Tatyasaheb Bhide's residence, or Bhidewada. He and his followers founded the Satyashodhak Samaj to achieve equal rights for people of lower castes. This organisation, which worked for the upliftment of the oppressed classes, was open to people of all religions and castes.

In 1919, the International Labour Organization was founded. The International Labour Organization (ILO), headquartered in Geneva, was the UN's first specialised agency. In response to a destructive war, it was founded in 1919 to pursue a vision based on the premise that universal, lasting peace can be established only if it is founded on decent treatment of workers.

On the morning of April 9, 2021, Prince Philip, Duke of Edinburgh, husband of Queen Elizabeth II of the United Kingdom and the other Commonwealth states, and the world's longest-serving royal consort, died in Windsor Castle at the age of 99. Prince Philip, Duke of Edinburgh was Queen Elizabeth II's husband. From Elizabeth's accession on 6 February 1952 until his death in 2021, he was the British monarch's consort, making him the longest-serving royal consort in history. Philip was born in Greece, into the royal families of Greece and Denmark; his family was exiled from the country when he was eighteen months old. 

On 5 April 2011, Hazare began a hunger strike to put pressure on the Indian government to implement a harsh anti-corruption law, The Lokpal Bill, 2011, as anticipated in the Jan Lokpal Bill, for the establishment of an ombudsman with the authority to deal with corruption in public places. Protests in favour of the fast erupted around the country. The fast came to an end on April 9, 2011, a day after the government agreed to Hazare's demands. The government published a gazette notice establishing a joint committee comprised of government and civil society leaders to write the law.

Christopher D'Olier Reeve was an American actor, director, and activist best known for his role as Superman in the 1978 film Superman and its first three sequels. Reeve met his future wife Dana Morosini, a singer and actress, in June 1987. They were living together by 1991, but Reeve couldn't bring himself to commit because of his parents' painful divorce and other failed marriages in his family. Reeve went to therapy for about a year after they almost divorced, primarily to talk through his fears about marriage. "I just put down my fork and asked her to marry me," he said one night during dinner. They married in April of 1992.

On 11 April 1996, Hugh Jackman married Deborra-Lee Furness at St. John's in Toorak, Victoria, a Melbourne suburb. They first met on the set of the Australian television show Correlli. Furness' engagement ring was designed by Jackman, and their wedding rings bore the Sanskrit inscription "Om paramar mainamar," which translates as "we dedicate our union to a greater source." Furness had two miscarriages before adopting two children, Oscar and Ava, with Jackman. Jackman lives in New York with his family.

India's first unmanned Earth satellite, Aryabhata. It was named after a prominent 5th century Indian astronomer and mathematician. The satellite was built in Peenya, near Bangalore, but was launched from within the Soviet Union on April 19, 1975, using a Russian-made rocket.

Jaya Bachchan is an Indian actress and politician who was born on April 9, 1948. She has been a Rajya Sabha member of the Samajwadi Party since 2004, and has served four terms. She is best known for her work in Hindi and Bengali cinema, but she is also known for promoting a natural acting style in mainstream and "middle-of-the-road" films. She has received numerous honours, including nine Filmfare Awards and the Padma Shri, India's fourth-highest civilian honour.

Ghanshyam Das Birla was a businessman from India and a member of the Birla family. Ghanshyam Das Birla was born on 10 April 1894 in Pilani, Jhunjhunu district, Rajputana, India, as a member of the Maheshwari Marwari community. Raja Baldevdas Birla was his father. Baldeo Das Birla travelled to Bombay in 1884 A.D. in search of new trade opportunities. In 1884, he founded Shiv Narian Baldeo Das in Bombay, and in 1897, he founded Baldeo Das Jugal Kishore in Calcutta. The companies began trading in silver, cotton, grain, and other commodities. Jugal Kishore, Rameshwar Das, Ghanshyam Das, and Braj Mohan were his four sons. The most successful was Ghanshyam Das.

Kasturbai Mohandas Gandhi was an Indian political activist who was born Kasturbai Gokuldas Kapadia on 11 April 1869 and died on 22 February 1944. In 1883, she married Mohandas Gandhi. With her husband and son, she was involved in the Indian independence movement in British India. Her husband had a significant influence on her. Every year on April 11, National Safe Motherhood Day is observed. Kasturba Gandhi's birthday is also celebrated on this day. Mohandas affectionately referred to her as 'Ba,' and in letters addressed her as Mrs. G, as in Gandhi

Swami Dayanand founded the Arya Samaj in Bombay on April 7, 1875, with ten principles that are beautifully based purely on God, soul, and nature. Arya Samaj (Sanskrit: "Society of Nobles") was a modern Hindu reform movement founded in 1875 by Dayananda Sarasvati with the goal of reestablishing the Vedas, the earliest Hindu scriptures, as revealed truth. Dayanand Saraswati's main message was for Hindus to return to their religion's roots, the Vedas. He believed that by doing so, Hindus would be able to improve the country's depressing religious, social, political, and economic conditions at the time.

Tipu Sultan led his force of almost 100,000 soldiers west and managed to get within 6 kilometres of Bednore by April 9th. Matthews' forces were quickly beaten in the field outside of Bednore. Matthews fled the town and retreated to the fort, which was immediately besieged by the army of Mysore. Matthews' force of 600 European men and 1,000 Indian sepoys lost 500 losses in minutes and fled to the fort, abandoning the town.

Morarji Ranchhodji Desai, who lived from 29 February 1896 to 10 April 1995, was an Indian independence activist and politician who served as India's fourth Prime Minister between 1977 and 1979, leading the Janata Party-led government. During his long political career, he held numerous important government positions, including Chief Minister of Bombay State, Home Minister, Finance Minister, and India's 2nd Deputy Prime Minister. Desai campaigned as a senior politician for the Janata Party in the 1980 General Election but did not run himself. He retired to Mumbai and died on April 10, 1995, at the age of 99.

Titanic, also known as the Royal Mail Ship (RMS) Titanic, British luxury passenger liner that sank during its maiden voyage from Southampton, England to New York City on April 14–15, 1912, killing approximately 1,500 passengers and ship personnel (see Researcher's Note: Titanic). One of the most well-known tragedies in modern history, it has inspired numerous stories, films, and a musical, as well as much scholarship and scientific speculation. On April 10, 1912, the Titanic set sail from Southampton, England, on its maiden and final voyage. The ship's construction began two years earlier in Belfast, Ireland, and was completed on March 31, 1912. On April 15th, 1912, just days after setting sail, the Titanic sank after colliding with an iceberg.

Hugh Marston Hefner (April 9, 1926 – September 27, 2017) was a magazine publisher in the United States. He was the founder and editor-in-chief of Playboy magazine, which featured revealing photographs and articles that sparked obscenity charges. The first issue of Playboy, which featured Marilyn Monroe in a nude calendar shoot, was released in 1953 and sold over 50,000 copies. Hefner grew the Playboy brand into a global network of Playboy Clubs. He also lived in luxury mansions with Playboy pals, who shared his wild partying lifestyle, which piqued the media's interest. He was a Democratic Party activist who advocated for First Amendment rights, animal rescue, and the restoration of the Hollywood Sign.

A gargantuan beast is devouring anything that strays too close to the heart of a giant elliptical galaxy called Messier 87, more than 50 million light-years away. Stars, planets, gas, and dust—nothing escapes the monster's grasp once it crosses a boundary known as the event horizon. The Event Horizon Telescope Collaboration published the first-ever snapshot of a black hole in 2019 after obtaining it in 2017 in galaxy M87, 6.5 billion times the mass of Earth and 55 million light-years away.

Kristen Jaymes Stewart (born April 9, 1990) is a film and television actress from the United States. She was the highest-paid actress in the world in 2012, and she has received numerous honours, including a British Academy Film Award and a César Award, as well as nominations for an Academy Award and a Golden Globe Award. Stewart was born and raised in Los Angeles to parents who both worked in the entertainment industry. At the age of 12, she received a Young Artist Award nomination for her role as the daughter of Jodie Foster's character in David Fincher's thriller Panic Room.

Ayesha Takia Azmi (born April 10, 1986) is a former Indian actress best known for her roles in Hindi films. In 2004, she won the Filmfare Best Debut Award for her performance in Taarzan: The Wonder Car. Ayesha Takia was born in Mumbai to a Muslim mother and a Hindu Gujarati father. She formerly attended St Anthony's Girls High School in Chembur. Farhan Azmi, her spouse, and she have a son. Apart from Bollywood, Takia participated in the Telugu Super 2005 film opposite Tollywood star Akkineni Nagarjuna, for which she was nominated for the Best Actress Telugu Filmfare Award. Her most recent triumph was Prabhu Deva's Wanted, which featured Salman Khan and was one of the year's biggest successes.

Sanjeev Kapoor (born 10 April 1964) is a well-known Indian celebrity chef, entrepreneur, and TV personality. Kapoor hosted the popular TV show Khana Khazana, Asia's longest running show of its kind, which was broadcast in 120 countries and had over 500 million viewers in 2010. He is also the world's first chef to own a 24-hour food and lifestyle channel, Food Food, which debuted in January 2011. Kapoor was born in Ambala in April 1964 and spent his childhood in several North Indian cities. After earning a Diploma in Hotel Management from the Institute of Hotel Management Catering & Nutrition, Pusa, New Delhi, he began his career in the hospitality industry in 1984. Alyona Kapoor is Kapoor's wife.

Ravindra Kaushik was born on April 11, 1952, and died in November 2001. He worked for the Research and Analysis Wing (R&AW). He is famously known as Black Tiger and is regarded as one of India's best spies of all time. He was able to break into the Pakistani armed forces' commissioned officer ranks. From 1979 to 1983, Kaushik worked as a spy for R&AW against Pakistan. Kaushik demonstrated his talent at a national level dramatic meet in Lucknow, Uttar Pradesh, which was witnessed by R&A Wing officials. He was contacted and offered a position as an undercover agent in Pakistan.

Lakshman Jhula is a suspension bridge that spans the Ganges. In 1930, the public could visit Rishikesh's Lakshman Jhula. It is 5 kilometres north-east of Rishikesh in the Indian state of Uttarakhand. Tapovan and Jonk are linked by the bridge. Tapovan is located on the west bank of the river in the Tehri Garhwal district, while Jonk is located on the east bank in the Pauri Garhwal district. The Lakshman Jhula is a pedestrian bridge that is also used by motorcycles. It is a Rishikesh landmark.