A typewriter is a mechanical or electromechanical device with a set of "keys" that, when pressed, cause characters to be printed on a medium, usually paper. For much of the 20th century, typewriters were indispensable tools in business offices and for many professional writers. By the end of the 1980s, word processor applications on personal computers had largely replaced the tasks previously accomplished with typewriters. Typewriters, however, remain popular in the developing world and among some niche markets.[citation needed]

By the mid-1800s, the increasing pace of business communication was creating a need for mechanization of the writing process. Stenographers and telegraphers could take down information at rates up to 130 words per minute, but a writer with a pen was limited to about 30 words per minute (the 1853 speed record).[4] From 1829 to 1870, many printing or typing machines were patented by inventors in Europe and America, but none went into commercial production.
Many old typewriters do not contain a separate key for the numeral 1 or the exclamation point, and some even older ones also lack the numeral zero. Typists who learned on these machines learned the habit of using the lowercase letter l for the digit 1, and the uppercase O for the zero. The exclamation point was a three-stroke combination of an apostrophe, a backspace, and a period. These characters were omitted to simplify design and reduce manufacturing and maintenance costs; they were chosen specifically because they were "redundant" and could be recreated using other keys. On modern keyboards, the exclamation point is the shifted character on the 1 key, a direct result of the heritage that these were the last characters to become "standard" on keyboards.