The most often used input devices is the keyboard.
The layout of the keys was borrowed from the typewriter with a number of new keys added.
Alphabet keys
The letters of alphabet and some punctuation marks are in three rows. The order of the keys is called QWERTY from the order keys on the top row.
This arrangement of the letters was inherited from the typewriter. It is not the most efficient layout. With the first typewriters, the typists had trouble with the mechanical keys jamming each other because the typists could strike the keys faster than the keys could get out of each others’ way. So the letters were arranged to slow the typists’ speed. Now that electric typewriters and computer keyboards no longer have mechanical keys, a more efficient layout could be used. But so many people are familiar and skilled with the told way that it doesn’t seem likely that the layout will change.
Alt
The Alt key doesn’t do anything by itself. But if you hold it down while pressing another key, the effect of that key may be different from usual. Exactly what will happen will depend on what program is running at the time.
Arrow keys
These four keys are used to move the cursor on the screen. The up and down arrows move the cursor up or down one line, the left and right arrows move the cursor one character.
Backspace
The backspace key erases the character on the left of the cursor and moves the cursor that direction, too.
Caps lock
When the caps lock key is on, pressing any alphabetic key will result in an upper case (capital) letter. The number and symbol keys are not affected, however. Watch out- this is different from typewriters.
Control
The control key does nothing all by itself. It must be pressed in combination with other keys. When used in combination, the control key changes the normal effect of a key. Exactly what will happen depends on the software in use at the time.
Delete
The delete key is used to erase the character just to the right of the cursor. Any text beyond the erased character is moved to the left.
End
The end key is a navigation key. It will the cursor to the end of the current line.
Enter
The enter key is used in several ways. In word processing, it acts like the return key on a typewriter by starting a new line. It is also used in place of a mouse click with buttons and drop-down menus.
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