Burroughs Adding Machine Ltd was established in 1886 as the American Arithmometer Company in St. Louis, Missouri by William Seward Burroughs. In 1885, Burroughs submitted a patent for an adding and listing machine with a full keyboard; the patent was approved in 1888 and the company’s first manufacturing branch was to open outside of the United States in Nottingham, United Kingdom. Early models such as the P100 were mostly basic in their operations and cranked by hand. They were also likely to be unreliable and inaccurate. Burroughs made improvements to the models in 1890-1 through the creation of an “oil-filled dashpot” in just seventy-two hours and these machines became known as The Burroughs Registering Accountant. The dashpot smoothed the operation of the machine allowing for accuracy and consistency. In celebration of this, Burroughs threw the faulty machines from a store-room window. In 1894 Burroughs began to market their machines directly with sales totalling 284 machines.

Although Burroughs died in 1898, the company moved to Detroit in 1904 and became known as the Burroughs Adding Machine Company. The company became the biggest adding machine company in America, with both an expansion in workforce and sales. Through time, the machines continued to evolve allowing for a greater range of capabilities than that of their predecessor. The P200 could subtract as well as add, the P300 allowed for two separate totals to be kept and the P400 had a moveable carriage. The P600 range allowed for limited programmability dependent on the positioning of the carriage. The range was gradually simplified with the addition of the “J” series which enabled single finger calculation and also the “c” series of manual and electrical-assisted comptometers.

In 1953, the Burroughs Adding Machine Company was renamed the Burroughs Corporation and began moving into computer products, initially for banking institutions. Burroughs purchased the Californian ElectroData Corporation in 1956, an amalgamation that would give way to the B205 tube computer. They then went on to produce the L and TC series range which became highly popular in the banking sector. Connected to mainframes, they sported a 1k memory and a golf ball printer. They also developed magnetic ink character recognition which enabled machines to process bank cheques; these were also connected to mainframes.

The late 1960s saw the birth of the Sensimatic, a highly advanced adding machine which could perform many business functions semi-automatically. This later developed into the Sensitronic which could store balances on a magnetic stripe which was part of the ledger card; the balance could then be read into the accumulator when the card was inserted into the carriage. As well as adding machines, Burroughs also branched out into the likes of typewriters.

Burroughs based their designs around “language-directed design”, favouring one or several high-level programming languages such as ALGOL, COBOL or FORTRAN. The 1960s also bore the invention of Burroughs’ large systems machines, the first series of which were the first machines with a virtual memory multi-programming operating system. These were succeeded by further series and the command interface eventually developed into a compiled structured language with declarations, statements and procedures called Work Flow Language. This series of computers are often considered to be revolutionary. Stack oriented processors provided a secure operating environment and the incorporation of multiple CPUs, multiple memory modules and multiple I/O and Data Comm processors permitted incremental and cost-effective growth of system performance and reliability. As such, their multiple abilities allowed Burroughs' machines to penetrate the banking sector.

Alongside accounting machines and other machines for use in the business sector, Burroughs also produced “small systems” that could be microprogrammed, military computers and, from 1982, personal computers. In September 1986, Burroughs Corporation merged with Sperry Corporation to form Unisys. The market for large systems soon shifted from business models to common servers, the company eventually dropped its business line of machines.