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A soft copy is an electronic copy of data viewed on a computer’s display screen or transmitted as an e-mail attachment.

QWERTY is the name of the standard keyboard.

A hard copy is a physical reproduction or representation of the data, such as a printed page or photograph.

Visual Display Unit and Printer

Printers are classified as impact printers and Non-impact printers.

Keyboard and Mouse

The devices which are used to input data and programs in the computer, are known as “Input Devices”.

An input device sends data to the computer but does not display (output) any information. An output device can print information or display from the computer but does not send any information (input) to the computer.

The devices that bring information OUT of a computer system are called output devices.

The printer is a hardcopy device and the Visual Display Unit is a softcopy device.

The cascading allows the user to use cout once only but use << operator several times to output many values.

The multiple use of << or >> in a one statement is known for cascading.

Cascading of output operator ( >>):

cout<<“ Hello “<<“ ISC

cout<< “Value of B=”<< b;

Cascading of input operator (>>):

int n1,n2,n3;

cin >> n1 >> n2 >> n3 ;

cin>>n1>>n2;

1. Input Operator: 

The statement cin>> num;

is an input statement and causes the program to wait for the user to type in a number. The operator >>is known as extraction or get from the operator. It takes the value from the keyboard and assigns it to the variable on its right.

2. Output Operator:

The statement cout<< “ the numbers”;

uses the cout identifier that represents the standard output stream ( screen) in C++. The operator < – Sounds incomplete -Author.

A mouse is something you push along your desktop to make a cursor (pointing device) move on your screen. So, what a mouse has to do is figure out how much you’re moving your hand and in which direction. There are two main kinds of mouse and they do this job in two different ways, either using a rolling rubber ball (in a ball type mouse) or by bouncing a light off your desk (in an optical mouse).

When you print something, your computer sends a vast stream of electronic data to your laser printer. An electronic circuit in the printer figures out what all this data means and what it needs to look like on the page. It makes a laser beam scan back and forth across a drum inside the printer, building up a pattern of static electricity. The static electricity attracts onto the page a kind of powdered ink called toner. Finally, as in a photocopier, a fuser unit bonds the toner to the paper.

Impact printer: Produces text and images when tiny wire pins on print head strike the ink ribbon by physically contacting the paper. 

Example: Dot-matrix printer 

Non-impact printer: Produces text and graphics on paper without actually striking the paper. 

Example: Inkjet, Laser.

Floppy disks are small, removable, media storage devices. They store data on a thin, circular magnetic film enclosed in a flat, square plastic jacket.

Floppy disk is a pocketbook version of the magnetic disk. It is a random access device available in size 3 1/2, 5 1/4 or 8 inches diameter. Storage capacities of 640 KB, 1.2 MB, 1.44 MB are typical. It is a cheap, durable, non-volatile storage option and reusable by writing over the previous data. Floppy disk is a circular plate coated with magnetic material. It is enclosed in a jacket made of a special fiber that allows for the air to cushion the disk when it is rotating at high speed and avoid wear and tear to the disk. 

Both the floppy and the jacket carry a central hole for the central spindle and a small circular hole near it. The beginning of tracks and sectors are signaled when the small circular holes in the jacket and the disk coincide. There is a write-protect notch on the jacket, which when closed by a sticker, seals the floppy and thus prevents any further writing. Then information can only be read from the floppy.

The read-write heads sense the information through the oblong window in the jacket, which exposes the disk to the head. Floppy is to be formatted with tracks and sectors before use. Directory and file indices are stored in ‘00’ track of ‘01’ sector onwards to ‘n’ the sector and proceed to‘01’ th sector of ‘02’ track, etc., Each track holds the same volume of information. Reading commences from ‘00’ tracks and writing starts from a sector as mentioned earlier.

(d) Processing

The basic organization of a computer does not consist of Keyboard.

Unorganized raw facts and figures given to a computer are collectively called Data.

(c)  Scanner

(c) Handheld