The Keyboard
The keyboard is the common data entry device in a computer system. It is also called the Standard Input Device. You should also note that it is the slowest of all the input devices to use. It works with the very low current to send electrical impulses to the CPU when you press a key. Because the low current there is very little risk of electric shock from a keyboard and safety precautions are not necessary when using one.
A typical keyboard is divided into 5 regions:
1. The Qwerty keyboard – This is the part of the keyboard that is used the most and gets its name from the first six letters of the top rows of the keys i.e. “Q, W, E, R, T, Y”. Note that this is only the case in the UK – other countries such as France have different key combinations reflecting their different use of letters. The layout of the keys was originally devised to actually slow typist down as the early typewriters were prone to getting jammed if the keys were hit too quickly. The average speed of a trained typist on a qwerty keyboard. Such as the shown above is up to six character per second.
2. The Function keys – this part of the keyboard is situated above the qwerty keyboard. These keys are given the symbols F1 to F12 and are really shortcut keys to operate actions in programs or in the computer’s memory system. For example, pressing the F4 key might be a shortcut to saving a document to disk in a common word processing package.
3. Editing keys – this part of the keyboard is situated to the right of the qwerty keyboard and is used to edit text or data in common programs. The edit keys are also used to move around the document (Page up or Page down) or go to the start (by depressing the Home key) or end (by depressing the end key).
4. The Cursor Control Keys – These keys represent a quick way to move the cursor (in. for example, a word processing program) and are often quicker to use than the mouse. They are not recommended for moving the cursor over large distances. Here the home, end or page up and page down keys should be used.
5. The Numeric Keyboard – this part of the keyboard is used mainly by the people in the financial services to enter large amounts of numerical data. The keys are duplicates of those above the Qwerty keyboard but are the positioned on the extreme right of the keyboard for ease of use with one hand.
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