Abstraction means giving only essential things and hiding unnecessary details. Encapsulation is the binding of data members and methods together in a capsule to avoid accidental changes to data from external users. i.e., encapsulation is the bundling of related algorithms and data.

The declaration of a 2-D array is data-type array_name[row-size][col-size];
In the above declaration, data-type refers to any valid C++ data-type, array_name refers to the name of the 2-D array, row-size refers to the number of rows and col-size refers to the number of columns in the 2-D array.

The selection statement means the statements are executed depends upon a condition. If a condition is true, a true block (a set of statements) is executed, otherwise a false block is executed. This statement is also called decision statement or selection statement because it helps in making decision about which set of statements are to be executed.
Types: (i) Two way branching, (ii) Multiway branching.

A programming language is a notation for expressing algorithms so that a computer can execute the algorithm.

In refinement, each statement is repeatedly expanded into more detailed statements in the subsequent levels.

(1) Hard disk
(2) CD
(3) DVD
(4) Pen drive

(i) Internet
(ii) Intranet

Different operating system used:
1. Single user, single Task Operating system
2. Multi user operating system
3. Multiprocessing operating system
4. Distributed Operating system

The ALU is a part of CPU where various computing functions are performed on data. ALU performs arithmetic operations such as addition, subtraction, multiplication, division and logical operations.

Paradigm means organizing principle of a program. It is an approach to programming. There are different approaches available for problem solving using computer. They are Procedural programming, Modular Programming and Object Oriented Programming.

The structure declared within another structure is called a nested structure
Example:
struct Student
{
int age;
float height, weight;
struct dob
{
int date;
char month[4];
int year;
};
}sl;

Given Code	Functional Code
v = 5; do; { total += v; cout << total; while v <= 10	int v = 5, total = 0; do { total + = v; cout << total; V++; } while (v<=10);

Touch Screen:
A touch screen is a display device that allows the user to interact with a computer by using the finger. It can be quite useful as an alternative to a mouse or keyboard for navigating a Graphical User Interface (GUI). Touch screens are used on a wide variety of devices such as computers, laptops, monitors, smart phones, tablets, cash registers and information kiosks. Some touch screens use a grid of infrared beams to sense the presence of a finger instead of utilizing touch-sensitive input.

Programming language, pseudo code, flowchart are notations for expressing algorithms.

(i) Single-user operating system
(ii) Multi-user Operating system
(iii) Distributed Operating system
(iv) Operating system
(v) Mobile Operating system.

(i) This algorithm is based on queuing technique. This is the basic logic of the FIFO algorithm.
(ii) Technically, the process that enters the queue first is executed first by the CPU, followed by the next and so on.
(iii) The processes are executed in the order of the queue (row).

Impact printers:
(i) Impact printer refers to the class of printers that work by banging a head or needle against an ink ribbon to make a mark on the paper.
(ii) Impact printers are very noisy.
(iii) These printers can print on multi-part.
Eg: Dot Matrix, Line printers.

(a) #include <iostream>
using namespace std;
#include <math.h>
#factorial function.
long int fact(int n)
{
long int f= 1;
for (int i = 1;i<n; i++)
f* = i;
return f
}
// main function
int main()
{
int x, y = 1;
float sum = 0;
cout<<"Enter the value for x:";
cin>>x;
for (int i=1;i<-6; i++)
{
sum = sum + y*((pow(x, 1))/fact(i));
y*=-1;
}
cout<<"Sum=" <<Sum<<endl;
cin.get():
return();
}
(b) #include <iostream>
using namespace std;
#include <math.h>
int main()
{
int M, L;
float sum = 0;
cout<<"Enter the value for M:";
cin>>M;
cout<<"Enter the number of terms";
cin>> L;
for (int i=1;i<=m; i++)
sum Sum + Pow(m,i)/i;
cout<<"Sum="<< Sum<<endl;
cin.get():
return 0;
}

divide (A, B)
-- inputs: A is an integer and \(B\ne 0\)
 --outputs: q and r such that A = q X B + r and
--0 < r < B
q:= 0,A
while r > B
q, r:= q + 1, r - B

Ans.(a)
Let a, b, c be the variables whose maximum value are 8L, 5L and 3L respectively.
Initial State

a, b, c: 4, 4,0
Specifications:
1 decant
2-inputs: a, b, c: =8,0,0
3-outputs: a, b, c: = 4, 4, 0
Algorithm:
Let us assume that a: = b denote oil in b is poured into a bottle until either "a" is full or "b" becomes empty.
1 decant (a, b, c)
2 a, b, c:=8,0,0
3 b:=a
4 --a, b, c: 3, 5, 0.
5 c:=b
6 --a, b, c: = 3, 2, 3
7 a:=c
8 -- a, b, c: = 6, 2,0
9 c:=b
10 --a, b, c:=6,0,2
11 b: a
12 a, b, c: = 1, 5, 2
13 c:=b
14 --a, b, c: 1, 4, 3
15 a: c
16 --a, b, c: = 4, 4,0

Booting of computer:
(i) An Operating system (OS) is a basic software that makes the computer to work. When a computer is switched on, there is no information in its RAM.
(ii) At the same time, in ROM, the pre-written program called POST (Power on Self Test) will be executed first. This program checks if the devices like RAM, keyboard, etc., are connected properly and ready to operate. If these devices are ready, then the BIOS (Basic Input Output System) gets executed. This process is called Booting.
(iii) Thereafter, a program called "Bootstrap Loader" transfers OS from hard disk into main memory. Now the OS gets loaded (Windows/Linux, etc.,) and will get executed. Booting process is of two types.
1) Cold Booting
2) Warm Booting
(iv) Cold Booting:
When the system starts from the initial state i.e. it is switched on, we call it cold booting or Hard Booting. When the user presses the power button, the instructions are read from the ROM to initiate the booting process.
(v) Warm Booting:
When the system restarts or when Reset button is pressed, we call it Warm Booting or Soft Booting. The system does not start from the initial state and so all diagnostic tests need not be carried out in this case. There are chances of data loss and system damage as the data might not have been stored properly.

(i) Basic components of computer :
The Basic components are I/O Unit, CPU, ALU, Control Unit, Storage Unit.
Input unit:
Input unit is used to feed any form of data to the computer. It can be stored in the memory unit for further processing.
Ex. Keyboard, Mouse, Scanner, Retinal scanner, Track ball.
Central processing unit:
CPU is the major component and it controls the operation of all other components such as memory, input and output units. The CPU has three components namely control unit, Arithmetic and logic unit (ALU) and memory unit.
Arithmetic and logic unit:
The ALU is a part of the CPU where arithmetic operations like addition, subtraction, multiplication, divisions and logical operations will takes place.
Control unit:
The control unit controls the flow of data between the CPU, memory and I/O devices. It also controls the entire operation of a computer.
Output unit:
An output device is a hardware component that conveys information to the user in an understandable form.
Ex. Monitor, printer, plotter
Memory unit:
The memory stores everything that computer works with. The memory unit is of two types namely primary memory and secondary memory. The primary memory stores the data and instructions temporarily. Whereas the secondary memory stores the data permanently. The primary memory is volatile and secondary memory is non-volatile.

The data and application that are stored and processed on multiple physical locations across the world over the digital network (internet/intranet). The Distributed Operating System is used to access shared data and files that reside in any machine around the world. The user can handle the data from different locations. The users can access as if it is available on their own computer.
The advantages of distributed Operating System are as follows:
1. A user at one location can make use of all the resources available at another location over the network.
2. Many computer resources can be added easily in the network
3. Improves the interaction with the customers and clients.
4. Reduces the load on the host computer.