   #copyright

Typewriter

2007 Schools Wikipedia Selection. Related subjects: Engineering

   Mechanical desktop typewriters, such as this Underwood Five, were long
   time standards of government agencies, newsrooms, and sales offices.
   They have been largely replaced by IBM Selectrics and newer electronic
   models. Models like this are occasionally still seen in urban sales
   offices that use paper invoices.
   Enlarge
   Mechanical desktop typewriters, such as this Underwood Five, were long
   time standards of government agencies, newsrooms, and sales offices.
   They have been largely replaced by IBM Selectrics and newer electronic
   models. Models like this are occasionally still seen in urban sales
   offices that use paper invoices.
   This Smith Premier typewriter, purchased around the end of the 19th
   century, was found abandoned in the Bodie ghost town. This early
   example had separate keys for upper- and lower-case letters.
   Enlarge
   This Smith Premier typewriter, purchased around the end of the 19th
   century, was found abandoned in the Bodie ghost town. This early
   example had separate keys for upper- and lower-case letters.

   A typewriter is a mechanical, electromechanical, or electronic device
   with a set of "keys" that, when pressed, cause characters to be printed
   on a document, usually paper.

   In the late 19th and the start of the 20th century a person who
   operated such a device was sometimes also called a typewriter but it
   then became more common to call the person a typist.

   For much of the 20th Century, typewriters were indispensable tools in
   business offices and for many (if not most) professional writers. By
   the 1980s, however, word processor applications on personal computers
   largely overtook the tasks previously done with typewriters. However,
   typewriters are still popular in the developing world, and among some
   niche markets.

   As of 2006, the following companies manufacture typewriters and
   accessories: Smith-Corona, Olivetti, Adler-Royal, Olympia, Brother, and
   Nakajima. Olivetti is the only western company to currently manufacture
   manual typewriters. All other current models are electronic.

History

Early Innovations

   Types in a 1920's typewriter
   Enlarge
   Types in a 1920's typewriter

   No one person can be said to have invented the typewriter. As with the
   light bulb, automobile, telephone, and telegraph, a number of people
   contributed insights and inventions that eventually resulted in
   commercially successful instruments. In 1714 Henry Mill obtained a
   patent in Britain for a machine that from the patent sounds similar to
   a typewriter, but nothing further is known. Other early developers of
   writing machines include Pellegrino Turri (1808), who also invented
   carbon paper. Many of these earliest machines, including Turri's, were
   developed to enable the blind to write.
   An index typewriter with a circular keyboard is one of many designs of
   early typewriters which did not become widely adopted. Enlarge
   An index typewriter with a circular keyboard is one of many designs of
   early typewriters which did not become widely adopted.

   In 1829 William Austin Burt patented a machine called the
   "Typographer." Like many other early machines, it is sometimes listed
   as the "first typewriter"; the Science Museum (London) describes it
   merely as "the first writing mechanism whose invention was documented,"
   but even that claim may be excessive, since Turri's machine is well
   known. Even in the hands of its inventor, it was slower than
   handwriting. Burt and his promoter John D. Sheldon never found a buyer
   for the patent, and it was never commercially produced. Because it used
   a dial to select the character instead of having an individual key for
   each character, it was an "index typewriter" rather than a "keyboard
   typewriter," if it is to be considered a typewriter at all. From 1829
   to 1870, many printing or typing machines were patented by inventors in
   Europe and America, but none went into commercial production. Charles
   Thurber developed multiple patents; his first, in 1843, was developed
   as an aid to the blind. See Charles Thurber's 1845 Chirographer, as an
   example.

   In 1855 the Italian Giuseppe Ravizza created a prototype typewriter
   called "Cembalo scrivano o macchina da scrivere a tasti." It was an
   advanced machine that let the user see the writing as it was typed.
   Fr. Azevedo's typewriter
   Enlarge
   Fr. Azevedo's typewriter

   Father Francisco João de Azevedo, a Brazilian priest, made his own
   typewriter in 1861 with poor materials, such as wood and knives. D.
   Pedro I, the Brazilian emperor, in that same year, presented a gold
   medal to Father Azevedo for this invention. Many Brazilian people as
   well as Brazilian federal government recognize Fr. Azevedo as the real
   inventor of the typewriter, a claim that has been the subject of
   controversy.

   The Austrian Peter Mitterhofer created a typewriter in 1864, but it was
   never produced commercially. Mitterhofer continued to improve his
   original model and created five different enhanced typewriters until
   1868.
   The Hansen Writing Ball, invented in 1865. This model is from 1870
   Enlarge
   The Hansen Writing Ball, invented in 1865. This model is from 1870

   In 1865 Rev. Rasmus Malling-Hansen of Denmark invented the Hansen
   Writing Ball, which went into commercial production in 1870 and was the
   first commercially sold typewriter. It was a success in Europe and was
   reported being used in offices in London as late as 1909. Additionally,
   Malling-Hansen used a solenoid escapement to return the carriage on
   some of his models and was responsible for the first "electric"
   typewriter. From the book Hvem er Skrivekuglens Opfinder?, written by
   Malling-Hansen's daughter Johanne Agerskov, we know that Malling-Hansen
   in 1865 made a porcelain model of the keyboard of his writing ball and
   experimented with different placements of
   Writing Ball: model from 1878
   Enlarge
   Writing Ball: model from 1878

   the letters to achieve the fastest writing speed. Malling-Hansen placed
   the letters on short pistons that went directly through the ball and
   down to the paper, and this, together with placement of the letters so
   that the fastest writing fingers struck the most frequently used
   letters, made the Hansen Writing Ball the first typewriter to produce
   text substantially faster than a person could write by hand.
   Malling-Hansen developed his typewriter further through the 1870s and
   1880s and made many improvements, but the writing head remained the
   same. On the first model of the writing ball from 1870, the paper was
   attached to a cylinder inside a wooden box. In 1874 the cylinder was
   replaced by a carriage, moving underneath the writing head. Then, in
   1875, the well-known, tall model was patented, and it was the first of
   the writing balls that worked without electricity. Malling-Hansen
   attended the world exhibitions in Vienna in 1873 and Paris in 1878. At
   both places, he received the first-prize medals for his invention.
   1868 patent drawing for the typewriter invented by Christopher L.
   Sholes, Carlos Glidden, and J. W. Soule.
   Enlarge
   1868 patent drawing for the typewriter invented by Christopher L.
   Sholes, Carlos Glidden, and J. W. Soule.

   In 1867 Christopher Sholes, Carlos Glidden, and Samuel W. Soule
   invented another typewriter. The patent (US 79,265) was sold for
   $12,000 to Densmore and Yost, who made an agreement with E. Remington
   and Sons (then famous as a manufacturer of sewing machines) to
   commercialize what was known as the Sholes and Glidden Type-Writer.
   Remington started production of their first typewriter on March 1,
   1873, in Ilion, New York. Another early typewriter manufacturer was
   Underwood.

   The ability to view what is typed as it is typed is taken for granted
   today. In all early keyboard typewriters, however, the typebars struck
   upwards against the bottom of the platen. Thus, what was typed was not
   visible until the typing of subsequent lines caused it to scroll into
   view. The difficulty with any other arrangement was ensuring that the
   typebars fell back into place reliably when the key was released. This
   was eventually achieved with ingenious mechanical designs, and
   so-called "visible typewriters" were introduced in 1895. Surprisingly,
   the older style continued in production as late as 1915.

Standardization

   By about 1920, the "manual" or "mechanical" typewriter had reached a
   more or less standardized design. There were minor variations from one
   manufacturer to another, but most typewriters followed the design noted
   below:

   Each key was attached to a typebar that had the corresponding letter
   molded into its other end. When a key was struck briskly and firmly,
   the typebar hit a ribbon (usually made of inked fabric) stretched in
   front of a cylindrical platen that moved back and forth. The paper was
   rolled around by the typewriter's platen, which was then rotated by a
   lever (the "carriage return" lever at the far left) to each new line of
   text. Some ribbons were inked in black and red, each a stripe half the
   width and the entire length of the ribbon. A lever on most machines
   allowed switching between colors for typing bookkeeping entries, where
   negative amounts had to be in red.

Electric designs

   Though electric typewriters would not achieve widespread popularity
   until nearly a century later, the basic groundwork for the electric
   typewriter was laid by the Universal Stock Ticker, invented by Thomas
   Edison in 1870. This device remotely printed letters and numbers on a
   stream of paper tape from input generated by a specially designed
   typewriter at the other end of a telegraph line.

   The first electric typewriter was produced by the Blickensderfer
   Manufacturing Company, of Stamford, Connecticut, in 1902. While never
   marketed commercially, this was the first known typewriter to use a
   typewheel rather than individual typebars, although the element was
   cylindrical rather than ball-shaped. The next step in the development
   of the electric typewriter came in 1909, when Charles and Howard Krum
   file a patent for the first practical teletype machine in 1909. The
   Krum's machine also used a typewheel rather than individual typebars.
   While innovative, neither of these machines reached the business or
   personal consumer.

   Electrical typewriter designs removed the direct mechanical connection
   between the keys and the element that struck the paper. Not to be
   confused with later electronic typewriters, electric typewriters
   contained only a single electrical component: the motor. Where the
   keystroke had previously moved a typebar directly, now it engaged
   mechanical linkages that directed mechanical power from the motor into
   the typebar. This was also true of the forthcoming IBM Selectric.

   IBM and Remington electric typewriters were the leading models until
   IBM introduced the IBM Selectric typewriter, which replaced the
   typebars with a spherical typeball (more correctly, "element"),
   slightly larger than a golf ball, with the letters molded on its
   surface. The Selectric used a system of latches, metal tapes, and
   pulleys driven by an electric motor to rotate the ball into the correct
   position and then strike it against the ribbon and platen. The typeball
   moved laterally in front of the paper instead of the former
   platen-carrying carriage moving the paper across a stationary print
   position.
   replaceable IBM typeballs with clip, 2 Euro coin to compare
   Enlarge
   replaceable IBM typeballs with clip, 2 Euro coin to compare

   The typeball design had many advantages, especially in eliminating of
   "jams" when more than one key was struck at once, and in the ability to
   change the typeball, allowing multiple fonts to be used in a single
   document. Selectric mechanisms were widely incorporated into computer
   terminals in the 1970s, because the typing mechanism was reasonably
   fast and jam-free; could produce very high quality output compared to
   competitors such as Teletype machines, could be initiated by a short,
   low-force mechanical action; did not require the movement of a heavy
   "type basket" in order to shift between lower- and upper-case; and did
   not require the platen roller assembly to move from side to side (which
   would be a problem with continuous-feed paper). The IBM 2741 terminal
   was a very popular example of a Selectric-based computer terminal, and
   similar mechanisms were employed as the console devices for many IBM
   System/360 computers. These mechanisms did use "ruggedized" designs
   compared to those in standard commercial typewriters.

   Later models of IBM Executives and Selectrics replaced inked fabric
   ribbons with "carbon film" ribbons that had a dry black or colored
   powder on a "once-through" clear plastic tape. These could be used only
   once but later models used a cartridge that was simple to replace. A
   side effect of this technology is that the text typed on the machine
   can be easily read from the used ribbon. This "feature" raised issues
   where the machines were used for preparing classified documents;
   ribbons had to be accounted for to ensure that typists didn't walk out
   with them in pockets or purses. A document reconstructed from a used
   carbon ribbon was portrayed as the key to solving a crime in an episode
   of Columbo.
   Electronic typewriter - the final stage in typewriters development. A
   1989 Canon Typestar 110
   Enlarge
   Electronic typewriter - the final stage in typewriters development. A
   1989 Canon Typestar 110

   A variation known as "Correcting Selectrics" introduced correction,
   where a sticky tape in front of the print ribbon could remove the
   black-powdered image of a typed character, and introduced selectable
   "pitch" so that the typewriter could be switched among pica ("10
   pitch", or 10 characters per inch) and elite ("12 pitch"), even in one
   document. Even so, all Selectrics were monospaced—each and every
   character was allotted the same horizontal space on the page. Although
   IBM had produced a successful typebar-based machine, the IBM Executive,
   with proportional spacing, no proportionally spaced Selectric office
   typewriter was ever introduced. There was, however, a much more
   expensive proportionally spaced machine called the Selectric Composer
   which was capable of right-margin justification and so was considered a
   typesetting machine rather than a typewriter, and the more reasonably
   priced IBM Electronic Typewriter 50, which was capable of proportional
   spacing but not justifying.

   The final major development of the typewriter was the "electronic"
   typewriter. Most of these replaced the typeball with a daisy wheel
   mechanism (a disk with the letters molded on the outside edge of the
   "petals"). A plastic daisy-wheel was much simpler and cheaper than the
   typeball but wore out more easily. Some electronic typewriters were in
   essence dedicated word processors with internal memory and cartridge or
   diskette external memory-storage devices. Unlike the Selectrics and
   earlier models, these really were "electronic" and relied on integrated
   circuits and multiple electromechanical components.

Computer/typewriter hybrids

   Towards the end of the commercial popularity of typewriters in the
   1980s, a number of hybrid designs combining features of computer
   printers and typewriters were introduced.

   These typically incorporated keyboards from existing models of
   typewriters and the printing mechanism of dot-matrix printers. The
   generation of teletypes with impact pin-based printing engines was not
   adequate for the demanding quality required for typed output. Newly
   developed, thermal transfer technologies used in thermal label printers
   had become technically feasible for typewriters.

   IBM produced a series of typewriters called Thermotronic with
   letter-quality output and correcting tape along with printers tagged
   Quietwriter. Brother extended the life of their typewriter product line
   with similar products. DEC meanwhile had the DECwriter.

   The development of these proprietary printing engines provided the
   vendors with exclusive markets in consumable ribbons and the
   possibility to use standardised printing engines with varying degrees
   of electronic and software sophistication to develop product lines.

   The increasing dominance of personal computers and the introduction of
   low-cost, truly high-quality, laser and inkjet printer technologies are
   replacing typewriters.

Typewriter legacy

   Today, with the proliferation of the personal computer with word
   processing software, typewriters would seem to have faded into
   near-obscurity. However typewriters were commonly used in professional
   offices (lawyers, doctors, schools, etc.) for specialized applications
   such as filling out pre-printed forms, addressing envelopes, and
   writing letters. However, in recent years computer programs have
   enabled computer users to accomplish most or all of these tasks.

   The monospaced, stark, and slightly uneven look of typewritten text can
   have some artistic appeal, and some people, young or old, prefer to use
   a typewriter.
   The QWERTY layout of typewriter keys became a de facto standard and
   continues to be used long after the reasons for its adoption have
   ceased to apply.
   The QWERTY layout of typewriter keys became a de facto standard and
   continues to be used long after the reasons for its adoption have
   ceased to apply.

   In some less developed countries, where personal computers are not
   ubiquitous, one may find public spaces with individuals who rent out
   their services as on-the-spot letter writers, accepting dictation from
   their customers, who may be illiterate or who simply do not own a
   typewriter. In Mexico, for example, such a thing can be seen daily on
   Calle Heroes de Cañonero in downtown Tampico.

Keyboard layout

   The 1874 Sholes & Glidden typewriters established the QWERTY layout for
   the letter keys. During the period in which Sholes and his colleagues
   were experimenting with this invention, other keyboard arrangements
   were apparently tried, but these are poorly documented. The tantalizing
   near-alphabetical sequence on the "home row" of the QWERTY layout
   (d-f-g-h-j-k-l) demonstrates that a straightforward alphabetical
   arrangement was the original starting point . The QWERTY layout of keys
   has become the de facto standard for English-language typewriter and
   computer keyboards. Other languages written in the Latin alphabet may
   use variants of the QWERTY layouts, such as the French AZERTY, the
   Italian QZERTY, the German QWERTZ, and the Portuguese HCESAR layouts.

   The QWERTY layout is certainly far from the most efficient, since it
   requires a touch-typist to move his or her fingers between rows to type
   the most common letters. A popular story suggests that it was used for
   early typewriters because it was inefficient; it slowed a typist down
   so as to reduce the frequency of the typewriter's typebars' wedging
   together and jamming the machine. A more likely explanation is that the
   QWERTY arrangement was designed to reduce the likelihood of internal
   clashing by placing commonly used combinations of letters farther away
   from each other inside the machine . This allowed the user to actually
   type faster without jamming. Unfortunately, no definitive explanation
   for the QWERTY keyboard has been found, and typewriter aficionados
   continue to debate the issue.

   A number of radically different layouts, such as the Dvorak keyboard,
   have been proposed to reduce the perceived inefficiencies of QWERTY,
   but these have not been able to displace the QWERTY layout; their
   proponents claim considerable advantages, but so far none has been
   widely used. The Blickensderfer typewriter with its DHIATENSOR layout
   may have possibly been the first attempt at optimizing the keyboard
   layout for efficiency advantages.

   Many old typewriters do not contain a separate key for the numeral 1,
   and some even older ones also lack the numeral zero. Typists learned
   the habit of using the lowercase letter l for the digit 1, and the
   uppercase O for the zero. Some still carry the habit of using the
   letter l instead of the numeral 1 with them when typing on a computer,
   sometimes leading to errors, especially when working with numerical
   data.

Computer jargon

   Several words of the 'typewriter age' have survived into the personal
   computer era. Examples include:
     * carbon copy – now in its abbreviated form "CC" designating copies
       of email messages (with no carbon involved, at least not until
       potential printouts);
     * cursor – a marker used to indicate where the next character will be
       printed
     * carriage return (CR) – indicating an end of line and return to the
       first column of text (and on some computer platforms, advancing to
       the next line)
     * line feed (LF), aka 'newline' – standing for moving the cursor to
       the next on-screen line of text in a word processor document (and
       on the eventual printout(s) of the document).

   Because the typebars of this typewriter strike upwards, the typist in
   this French postcard, c. 1910, could not have seen characters as they
   were typed.
   Because the typebars of this typewriter strike upwards, the typist in
   this French postcard, c. 1910, could not have seen characters as they
   were typed.

Correction methods

   According to the standards taught in secretarial schools in the mid-
   1900s, a business letter was supposed to have no mistakes and no
   visible corrections. Accuracy was prized as much as speed. Indeed,
   typing speeds, as scored in proficiency tests and typewriting speed
   competitions, included a deduction of ten words for every mistake that
   was made.

   Corrections were, of course, necessary, and a variety of methods and
   technologies were used.

   The traditional method involved the use of a special typewriter eraser.
   The typewriter eraser was made of fairly hard, stiff rubber, containing
   abrasive material. It was in the shape of a thin, flat disk, approx. 2
   inches (50 mm) in diameter by 1/8 inch (3 mm) thick allowing for the
   erasure of individual typed letters. Business letters were typed on
   heavyweight, high-rag-content bond paper, not merely to provide a
   luxurious appearance, but also to stand up to erasure. Typewriter
   erasers were equipped with a brush for brushing away eraser crumbs and
   paper dust, and using the brush properly was an important element of
   typewriting skill, because if erasure detritus fell into the
   typewriter, a very small buildup could cause the typebars to jam in
   their narrow supporting grooves.

   Erasing a set of carbon copies was particularly difficult, and called
   for the use of a device called an eraser shield to prevent the pressure
   of erasure on the upper copies from producing carbon smudges on the
   lower copies.

   Paper companies produced a special form of typewriter paper called
   erasable bond (for example, Eaton's Corrasable Bond). This incorporated
   a thin layer of material that prevented ink from penetrating and was
   relatively soft and easy to remove from the page. An ordinary soft
   pencil eraser could quickly produce perfect erasures on this kind of
   paper. However, the same characteristics that made the paper erasable
   made the characters subject to smudging due to ordinary friction and
   deliberate alteration after the fact, making it unacceptable for
   business correspondence, contracts, or any archival use.

   In the 1950s and 1960s, correction fluid made its appearance, under
   brand names such as Liquid Paper, Wite-Out and Tipp-Ex. This was a kind
   of opaque white fast-drying paint which produced a fresh white surface
   onto which a correction could be re-typed. However, when held to the
   light, the covered-up characters were visible, as was the patch of dry
   correction fluid (which was never perfectly flat, and never a perfect
   match for the colour, texture, and luster of the surrounding paper).
   The standard trick for solving this problem was photocopying the
   corrected page, but this was possible only with high quality
   photocopiers, and was not practical with color letterheads. (However,
   high quality typists were smart enough to place the color letterhead
   stock in the copier, and photocopy the corrected
   typed-text-only-on-plain-paper document onto the colour letterhead.)

   Dry correction products (such as correction paper) under brand names
   such as "Ko-Rec-Type" were introduced in the 1970s and functioned like
   white carbon paper. A strip of the product was placed over the letters
   needing correction, and the incorrect letters were retyped, causing the
   black character to be overstruck with a white overcoat. Similar
   material was soon incorporated in carbon-film electric typewriter
   ribbons; like the traditional two-colour black-and-red inked ribbon
   common on manual typewriters, a black/white correcting ribbon became
   commonplace on electric typewriters.

   The pinnacle of this kind of technology was the IBM Electronic
   Typewriter series. These machines, and similar products from other
   manufacturers, used a separate correction ribbon and a character
   memory. With a single keystroke, the typewriter was capable of
   automatically reversing and overstriking the previous characters with
   minimal marring of the paper. White cover-up or plastic lift-off
   correction ribbons are used with fabric ink or carbon film typing
   ribbons, respectively.

Typing speed records and speed contests

   During the 1920s through 1940s, typing speed was an important
   secretarial qualification and typing contests were popular, publicized
   by typewriter companies as promotional tools.

   As of 2005, Barbara Blackburn is the fastest typist in the world,
   according to The Guinness Book of World Records. Using the Dvorak
   Simplified Keyboard, she has maintained 150 word/min for 50 min and 170
   word/min for shorter periods and has been clocked at a peak speed of
   212 word/min. Blackburn, who failed her typing class in high school,
   first encountered the Dvorak keyboard in 1938, quickly learned to
   achieve very high speeds, and occasionally toured giving speed-typing
   demonstrations during her secretarial career. She appeared on The David
   Letterman Show and was deeply offended by Letterman's comedic treatment
   of her skill.

   Popular software named " Mavis Beacon Teaches Typing" had led many
   people to assume that there is a woman named Mavis Beacon who is a very
   good typist. In reality, Mavis Beacon is a fictional promotional
   character.

Forensic identification

   Because of the tolerances of the mechanical parts, slight variation in
   the alignment of the letters and their uneven wear, each typewriter has
   its individual "signature" or " fingerprint", allowing a typewritten
   document to be tracked back to the typewriter it was produced on. In
   the Eastern Bloc, typewriters (together with printing presses, copy
   machines, and later computer printers) were a controlled technology,
   with secret police in charge of maintaining files of the typewriters
   and their owners. (In the Soviet Union, the organization in charge of
   typewriters was the First Department of the KGB.) This posed a
   significant risk for dissidents and samizdat authors. This method of
   identification was also used in the trial of Alger Hiss.

   Black/white computer printers have their "fingerprints" as well, but to
   lesser degree. Modern colour printers and photocopiers typically add
   printer identification encoding -- a steganographic pattern of
   minuscule yellow dots, encoding the printer's serial number -- to the
   printout.

   Other forensic identification method can involve analysis of the ribbon
   ink.

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