Financial markets have long paid for faster information. In 1841, the Mercantile Exchange began selling proprietary business data in the United States. Paul Julius Reuter launched news and stock-price services in the following decade, with pigeons carrying paper quotations between Aachen and Brussels. Edward Calahan introduced a telegraphic ticker in 1867, and Thomas Edison patented an improved version in 1871.

The Dow Jones Industrial Average arrived in 1896 with 12 companies from sectors including gas, oil, coal and electricity. Messengers carried prices from trading floors to brokerage offices. By the first official New York ticker-tape parade in 1919, telegraphy had become the main rapid channel for stock information in Western Europe and the United States. Quotron introduced electronic quote screens in 1960, followed by more services for distributing market data.

Michael Bloomberg entered the field in 1981 after leaving Salomon Brothers. He founded Innovative Market Systems, or IMS, with Thomas Secunda, Duncan MacMillan and Charles Zegar. Bloomberg brought a Johns Hopkins electrical engineering degree, a Harvard MBA and experience building computerized financial systems at Salomon. His company aimed to combine current data with calculations based on historical records.

IMS first built the Market Master, a monochrome CRT terminal with a custom keyboard and a communications controller linked to a private network. The launch product covered U.S. government bond prices and bond calculations. Merrill Lynch became the sole client, investing $30 million, about $110 million today, for a 30 percent stake and five years of exclusive terminal rights. It waived the exclusivity in 1984. The first 22 terminals reached Merrill in 1982, during the global recession of 1981-82. Electronic trading was spreading, interest rates were becoming more flexible in the United States, and volatile bond prices increased demand for better valuation tools.

Five years after launch, IMS became Bloomberg LP and the Market Master acquired its familiar name. The system used a closed network because commercial internet access did not yet exist. A cable connected the hand-assembled Chiclet keyboard to a Bloomberg Controller, which used a dedicated phone line to reach a local hub. Central computers stored the data and handled most calculations. Color-coded finance keys gave users direct commands for market data, analysis and trading.

Bloomberg added a trackball in 1990. The following major keyboard design added a speaker, telephone connections, headphone and microphone ports. Instant Bloomberg enabled messaging between terminal users. By 1996, keyboards supported 23 languages. Fingerprint readers appeared for login authentication in the early 2000s. Bloomberg also built its own news operation in 1990 after concerns that Dow Jones might withdraw its news access. Matthew Winkler led a team of 12 reporters. The later media business expanded to Bloomberg Businessweek, Bloomberg Radio and Bloomberg Television.

The subscription combined hardware, a private network and financial services. A single terminal cost $1,600 per month in 1999, with a minimum two-year contract and lower prices for additional units. Current annual pricing is above $32,000 and has run slightly below inflation. Open Bloomberg software arrived in 1995 for customers’ own PCs. Bloomberg stopped leasing dedicated terminals in 2000, and mobile apps later brought terminal functions to phones and tablets.

The terminal therefore became a broader environment for data, analysis, news, communication and trading. The move away from fixed hardware changed the physical culture of financial work, while older keyboards became museum objects. The Smithsonian’s National Museum of American History holds several examples, including object 2014.0012.02, used by Bill Gross at Pacific Investment Management during the 1990s and 2000s. Gross cofounded PIMCO in 1971 and helped build it into a $2 trillion bond firm. His login and password remain taped to the keyboard.

IEEE Spectrum published the account by Allison Marsh as part of its Past Forward series. An abridged version appeared in the October 2026 print issue. Other Bloomberg keyboards are held by institutions including the Computer History Museum.