Musk was born in Pretoria, a member of the South African Musk family, and briefly attended the University of Pretoria before immigrating to Canada at age 18, acquiring citizenship through his Canadian-born mother. Two years later, he matriculated at Queen's University at Kingston in Canada. Musk later transferred to the University of Pennsylvania and received bachelor's degrees in economics and physics. He moved to California in 1995 to attend Stanford University, but dropped out after two days and, with his brother Kimbal, co-founded online city guide software company Zip2. The startup was acquired by Compaq for $307 million in 1999. That same year, Musk co-founded X.com, a direct bank. X.com merged with Confinity in 2000 to form PayPal. In October 2002, eBay acquired PayPal for $1.5 billion. Using $100 million of the money he made from the sale of PayPal, Musk founded SpaceX, a spaceflight services company, in 2002.

In 2004, Musk was an early investor in electric vehicle manufacturer Tesla Motors, Inc. (later Tesla, Inc.). He became the company's chairman and product architect, assuming the position of CEO in 2008. In 2006, Musk helped create SolarCity, a solar-energy company that was acquired by Tesla in 2016 and became Tesla Energy. In 2013, he proposed a hyperloop high-speed vactrain transportation system. In 2015, he co-founded OpenAI, a nonprofit artificial intelligence research company. The following year, Musk co-founded Neuralink—a neurotechnology company developing brain–computer interfaces—and The Boring Company, a tunnel construction company. In 2018, the U.S. Securities and Exchange Commission (SEC) sued Musk, alleging that he had falsely announced that he had secured funding for a private takeover of Tesla. To settle the case, Musk stepped down as the chairman of Tesla and paid a $20 million fine. In 2022, he acquired Twitter for $44 billion. He subsequently merged the company into newly created X Corp. and rebranded the service as X the following year. In March 2023, Musk founded xAI, an artificial intelligence company.

Musk has expressed views that have made him a polarizing figure.[5] He has been criticized for making unscientific and misleading statements, including COVID-19 misinformation and appearing to endorse antisemitic conspiracy theories, the latter of which he later apologized for. His ownership of Twitter has been similarly controversial, being marked by layoffs of large numbers of employees, an increase in hate speech, misinformation and disinformation posts on the website, and changes to Twitter Blue verification.

The first guinea was produced on 6 February 1663 (361 years ago); a proclamation of 27 March 1663 made the coins legal currency. One troy pound of 11⁄12 (0.9133)[citation needed] fine gold (22 carat or 0.9167 pure by weight) would make 44+1⁄2 guineas,[5] each thus theoretically weighing 129.438 grains (8.385 grams crown gold, 7.688 grams fine gold, or 0.247191011 ozt (troy ounces) fine gold).

The coin was originally worth twenty shillings (one pound), but an increase in the price of gold during the reign of King Charles II led to the market trading it at a premium. The price of gold continued to increase, especially in times of trouble, and by the 1680s, the coin was worth 22 silver shillings. Indeed, in his diary entries for 13 June 1667, Samuel Pepys records that the price was 24 to 25 shillings.

The diameter of the coin was 1 in (25.4 mm) throughout Charles II's reign, and the average gold purity (from an assay done in 1773 of samples of the coins produced during the preceding year) was 0.9100. "Guinea" was not an official name for the coin, but much of the gold used to produce the early coins came from Guinea (largely modern Ghana) in West Africa.[7]

The coin was produced every year between 1663 and 1684, with an elephant appearing on some coins[4] each year from 1663 to 1665 and 1668, and the elephant with a howdah on other coins minted from 1674 or 1675 onwards. The elephant, with or without a howdah, was the emblem of the Royal African Company (RAC), which had been granted a monopoly on English trade with Africa in slaves, gold and other goods, from 1672 until 1698; gold imported from Africa by the RAC bore the elephant emblem beneath the monarch's head on the coin.