i. Punch Cards

• In the beginning of the computer era, text among all kinds of data was inserted into a computer system by directly manipulating the memory (for example by rewiring an array of contacts) and therefore binary.
• The first step in the direction of more natural text input were punch cards, simple cards made of stiff cardboard with (most commonly) 80 columns of defined positions printed on them.
• To represent data with such a card, rectangular bits of paper needed to be punched out at these positions.
• Thus, each position in a column represents one bit of the binary number stored in column.
• So cards could save up to 80 characters (one line) of text and were not only used as text input devices but also as data recording media.
• Users could now enter data by typing on a machine called "keypunch", which punched out the according bits of paper, and thus in a much faster and more intuitive way than before.
• The keyboard-layout of such a machine was adopted from traditional typewriters (plus some keys for card-management) and so nearly the same as on modern keyboards.

ii. Keyboards

There are three keyboard layouts:

1. QWERTY layout
2. Dvorak layout

3. ABCDE style Keys

   • The square keys are ½ inch.
   • The spacing between the keys is ¼ inch.
   • The keys are slight concave in surface.
   • It requires 40 to 125 grams force to activate.
   • 3 to 5 mm displacement.
   • Tactile and audible feedback is important.
   • Certain keys should be larger, such as ENTER, CTRL, SHIFT etc.
   • Some keys require state indicator, such as lowered position or light indicator. For example: CAPS LOCK.
   • Key labels should be larger, meaningful and permanent.
   • There are two more keys:
   • Function keys
   • Cursor movement keys

iii. Stylus

• This matter is especially of significance with the small displays of PDAs, where the keys become so tiny, that even small fingers couldn't operate them.
• Also the usage of a stylus with the on-screen keyboard doesn't really improve this situation very much. But used in a different technology, the stylus can be used as a quite powerful text input device.

iv. Glove

• An even more mobile way of entering text is the usage of special data-gloves. These devices are used with one or both hands to enter text either by measuring accelerations/rotations of the forearm and flexations of the fingers (gesture recognition) or in a more traditional way by working as a keyboard, whose buttons are attached to the glove - or combinations of these.
• Gloves, which are able to recognize gestures could proof especially for disabled people, who depend on communication through sign language, as extremely valuable; actually built prototypes and commercial products, however, suffered from a very little set of gestures the systems could understand and were quite expensive, but achieved good input-speeds.
• Gloves with attached buttons are much cheaper to build and need no extra computations, but are restricted to a small number of keys; therefore the simple mapping "one key (plus Shift/Control) -> one character" of ordinary keyboards cannot be used.
• Instead a technique called "chording" seems suitable: A character is typed by simultaneously pressing multiple buttons like musicians playing a chord on a trumpet.
• In this way, it is possible to type all standard letters plus some control inputs (e.g. <space> or <return>) with just one button at each finger of one glove by just pressing the fingertips on any surface; with two gloves of this kind there are far more possible input-combinations than a common keyboard provides - and a user is able to remember.
• Alternatively additional shifting-keys reachable for the thumb can enlarge the amount of typable characters.