Another important part of computer history is the humble keyboard which is still the prime input device of most computers. As early as 1711 Henry Mill, an Englishman, described a mechanical means of printing text on paper a character at a time. In 1829 the American William Burt was granted the first US patent for a typewriter, although his machine was not practical. It wasn’t until 1867 that three Americans, Sholes, Gliddend and Soule invented their Type-Writer, the forerunner of the modern typewriter. One of the problems encountered by Sholes was the tendency of his machine to jam when digraphs such as “th” and “er” were typed. Hitting the “t” and “h” keys at almost the same time caused the letters “t” and “h” to strike the paper simultaneously and jam. His solution was to arrange the letters on the keyboard to avoid the letters of digraphs being located side by side. This layout has continued until today and is now described by the sequence of the first six letters on the left of the top row – QWERTY. Since the same digraphs do not occur in different languages, the layout of a French keyboard is different to that of an English keyboard. It is reported that Sholes made it easy to type “type writer” by putting all these characters on the same row. 

Another enabling technology that played a key role in the development of the computer was the tabulating machine – a development of the mechanical calculator that processes data on punched cards. One of the largest data processing operations carried out in the USA during the 19^th Century was the US census. A census involves taking the original data, sorting and collating it, and tabulating the results – all classic data preparation operations Because of the shear volume of data involved, people attempted to automate data processing. In 1872 Colonel Charles W. Seaton invented a device to mechanize some of the operations involved in processing census data. 

In 1879 Herman Hollerith became involved in the evaluation of the 1880 US Census data. He devised an electric tabulating system that could process data stored on cards punched by clerks from the raw census data. Hollerith's electric tabulating machine could read cards, tabulate the information on the cards (i.e., count and record), and then sort the cards. These tabulators employed a new form of electromechanical counting mechanism. Moreover, punched cards reduced human reading errors and provided an effectively unlimited storage capacity. By copying cards, processing could even be carried out in parallel. During the 1890s and 1900s, Hollerith made a whole series of inventions and improvements, all geared towards automatic data collection, processing, and printing. 

The company Hollerith founded, Hollerith Tabulating Company, eventually became one of the three that made up the Calculating-Tabulating-Recording (C-T-R) company in 1914, and eventually was renamed IBM in 1924. 

Note how three threads converged to make the computer possible: Babbage’s calculating machines that perform arithmetic (indeed, even scientific) calculations; communications technology that laid the foundations for electronic systems and even networking; and the tabulator because it and the punched card media provided a means of controlling machines and inputting data into them, and storing information. Moreover, the tabulator helped lay the foundations of the data processing industry.