The predefined function getchar() is used to get a single character from keyboard and putchar() functions is used to display it.

Declaration is a process to instruct the compiler to allocate memory as per the type that is specified along with the variable name.

++ (Plus, Plus) Increment Operator. -- (Minus, Minus) Decrement operator. An increment or decrement operator acts upon a single operand and returns a new value. Thus, these operators are unary operators. The increment operator adds 1 to its operand and the decrement operator subtracts 1 from its operand.

TSCII (Tamil Script Code for Information Interchange) is the first coding system to handle our Tamil language in an analysis of an encoding scheme that is easily handled in electronic devices, including non-English computers. This encoding scheme was registered in IANA (Internet Assigned Numbers Authority) unit of ICANN.

A cookie (also called HTTP cookie, web cookie, Internet cookie, browser cookie, or simply cookie) is a small piece of data sent from a website and stored on the user's computer memory (Hard drive) by the user's web browser while the user is browsing internet.

Cracking is where someone edits a program source so that the code can be exploited or modified. "Cracking" means trying to get into computer systems in order to steal, corrupt, or illegitimately view data.

Private visibility mode	Public visibility mode
When a base class is inherited with private visibility mode the public and protected members of the base class become 'private' members of the derived class.	When a base class is inherited with public visibility mode, the protected members of the base class will be inherited as protected members of the derived class and the public members of the base class will be inherited as public members of the derived class.

The derived class is a power packed class, as it can add additional attributes and methods and thus enhance its functionality.

Inheritance is one of the most important features of Object Oriented Programming. In object- oriented programming, inheritance enables new class and its objects to take on the properties of the existing classes.

Function overloading is not only implementing polymorphism but also reduces the number of comparisons in a program and makes the program to execute faster. It also helps the programmer by reducing the number of function names to be remembered.

Operator that are not overloaded are follows
1. scope operator::
2. sizeof
3. member selector.
4. member pointer selector *
5. ternary operator?:

The ability of the function to process the message or data in more than one form is called as function overloading. In other words function overloading means two or more functions in the same scope share the same name but their parameters are different.

The purpose of the destructor is to free the resources that the object may have acquired during its lifetime. A destructor function removes the memory of an object which was allocated by the constructor at the time of creating a object.

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.

Class	Object
Class is a blue print or template from which objects are created.	Object is an instance of a class.
Class doesn't allocate memory when it is created.	Objects allocate memory when it is created.
Class is a logical entity.	Object is a physical entity.

Values can be assigned to structure elements similar to assigning values to variables. Values can be assigned directly as similar to assigning values to Arrays.

Array	Structure
It is a collection of variables of same datatype referenced by a common name.	It is a collection of variables of different datatype referenced by a common name.

Structure is a user-defined which has the combination of data items with different data types. This allows to group of variables of mixed data types together into a single unit. The structure provides a facility to store different data types as a part of the same logical element in one memory chunk adjacent to each other.

Accessing each element of an array at least once to perform any operation is known as "Traversal". Displaying all the elements in an array is an example of "traversal".

(i) A local variable is defined within a block. A block of code begins and ends with curly braces { }.
(ii) The scope of a local variable is the block in which it is defined.
(iii) A local variable cannot be accessed from outside the block of its declaration.
(iv) A local variable is created upon entry into its block and destroyed upon exit

Void type has two important purposes:
(I) To indicate the function does not return a value
(ii) To declare a generic pointer

The strelen() takes a null terminated byte string source as its argument and returns its length. The length does not include the null(\0) character.

Output:
2 4 6 8 10.

Null statement
The "null or empty statement" is a statement containing only a semi colon. It takes the following
form:
;// it is a null statement.
Null statement are commonly used as place holders in iteration statements or as statements on which to place labels at the end of compound statements or functions.
Compound statement
C++ allows a group of statements enclosed by pair of braces (). This group of statements is called as a compound statement or a block.
The general format of compound statement is:
{
statement 1;
statement 2;
statement 3;
}
for example:
{
int a,b;
a-8;
b=a+8;
}

Reference variable in C++ is alias for existing variable. They store nothing but the address of the variable used at the time of its declaration. It is important to assign the reference variable at the time of declaration, else it will show an error.

Setw manipulator sets the width of the field assigned for the output. The field width determines the minimum number of characters to be written in output.
Syntax: setw(number of characters)

Keywords are the reserved words which convey specific meaning to the C++ compiler. They are the essential elements to construct C++ programs. Most of the keywords are common to C, C++ and Java. Keywords are reserved and cannot be used as identifiers.

C++ program statements are constructed by many different small elelments such as commands, variables, constants and many more symbols called as operators and punctuators. Individual elements are collectively called as Lexical units or Lexical elements or Tokens. C++ has the following tokens:
(i) Keywords
(ii) Identifiers
(iii) Literals
(iv) Operators
(v) Punctuators

It is a multi-tasking and multi user operating system designed for real time based applications such as robotics, weather and climate prediction software etc.,

Pseudo code is a notation similar to programming languages.

Multiple applications which can be executed simultaneously in Windows is known as Multitasking.

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

Conditional Statement	Iterative Statement
Statements are executed only once when the condition is true.	Iterative statement repeatedly evaluates a condition and executes a statement until it becomes false.
If condition statement.	While condition statement.

A loop invariant is a condition [among program variables] that is necessarily true immediately before and immediately after, each iteration of a loop. A loop invariant is some condition that holds for every iteration of the loop.

In iteration, the loop body is repeatedly executed as long as the loop condition is true. Each time the loop body is executed, the variables are updated.
However, there is also a property of the variables which remains unchanged by the execution of the loop body. This unchanging property is called the loop invariant.

statement	condition
A statement is a phrase that commands the computer to do an action.	A condition is a phrase that describes a test of the state.
In flow chart rectangular box is used	In flow chart diamond box is used
Ex. x: = 5	Ex. If C SI else S2

11011110101110₂
Groups in fours          ​\(\overline { 11 } \)  \(\overline { 0111 } \)  \(\overline { 1010 } \)  \(\overline { 1110 } \)
Convert each number  3      7         A        E 
= 37AE₁₆ 

The system bus is a collection of wires as communication channels between the Microprocessor and other devices which is the collection of address bus, data bus and control bus.

USB 3.0 is the third major-version of the Universal Serial Bus (USB) standard to connect computers with other electronic gadgets. USB 3.0 can transfer data up to 5 Giga byte/second.

Extended Binary Coded Decimal Interchange Code (EBCDIC) is an 8-bit character-coding scheme used primarily on IBM computers.

(i) One's complement of 1010₂ is 0101₂ (replace 1by 0 and 0 by 1)
(ii) One's complement of 100101₂ is 011010₂

Decimal, octal, binary and hexadecimal number systems are called Positional value system.

It is extremely fast memory would store data that is frequently accessed and if possible, the data that is closer to it. This helps to achieve the fast response time.

The radix of Decimal is 10, Binary is 2, Octal is 8 and Hexadecimal is 16

(i) Numbers
(ii) Text
(iii) Graphics
(iv) Animations
(v) Audio
(vii) Video etc

The Find command on the Start menu to quickly search your entire computer or a specific folder or drive.

It is the time required to read or write data in a proper memory location or to retrieve stored data from the storage unit.

A decoder, a digital circuit is used to point to the specific memory location where the word can be located.

Title bar, Menu bar, Scroll bars, Status bar, Borders, Work space and Comers.

Multiple applications which can execute simultaneously in windows is known as "Multi tasking".

(i) The vertical bar of icons on the left side of the desktop is called the Launcher.
(ii) The Launcher provides easy access to applications, mounted devices, and the Trash.

If the hardware is not detected, a particular pattern of beeps will inform about the error. An error found in the POST is usually fatal (that is, it causes current program to stop running) and will halt the boot process, since the hardware check is absolutely essential for the computer's functions.

Pictures on a monitor are formed with picture elements called PIXELS.

The screen monitor works with the VGA (Video Graphics Array). The video graphics card helps the keyboard to communicate with the screen. It acts as an interface between the computer and display monitor. Usually, the recent motherboard incorporates built-in video card.

Natural Language Processing is the ability of a computer program to understand human language. It is a component of artificial intelligence.

A mobile OS controls a mobile device and its design supports wireless communication and different types of mobile applications.

An operating system allows a single user to perform a task at a time. It is called as Single user and single Task operating system.

A + (B + C) = ( A + B) + C
A. (B. C) = (A . B) .C

Boolean algebra is a mathematical discipline that is used for designing digital circuits in a digital computer. It describes the relation between inputs and outputs of a digital circuit.

1. --minimum (a,b)
2. -- inputs: a, b are real numbers.
3. --output: result: minimum (a,b)

An algorithm is a step by step sequence of statements intended to solve a problem. An algorithm starts execution with the input data, executes the statements and finishes execution with the output data.

Save	Save as
This will save the document without asking for a new name or location. It will over- write the original.	This will prompt to save the document using a dialog box. You will have the ability to change the file name and/or location. If you choose the same file name and location it will over-write the original. Your working document will be the one you just saved.

File Extension is the second part of the file name. It succeeds the decimal point in the file name. It is used to identify the type of file and it is normally upto 3 to 4 characters long.
Ex. 1. exe,2. html.

(i) BCD - Binary Coded Decimal.
(ii) EBCDIC - Extended Binary Coded Decimal Interchange Code.
(iii) ASCII - American Standard Code for Information Interchange
(iv) Unicode.
(v) ISCII - Indian Standard Code for Information Interchange

Step 1: Convert given Decimal number into Binary
Step 2: Check if the binary number contains 8 bits if less add 0 at the left most bit, to make it as 8 bits.
Step 3: Invert all bits (i.e. Change 1 as 0 and 0 as 1).

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

Multiprocessing is one of the features of operating system. It has two or more processors for a single running process. Each processor works on different parts of the same task or two or more different tasks.

A Multi-user Operating system is a computer operating system (OS) that allows multiple users on different computers or terminals to access a single system with one OS on it.

HDMI (High Definition Multimedia Interface) is an audio/video interface which transfer the uncompressed video and audio data from a video controller, to a compatible computer monitor, LCD projector, digital television, etc.

Instruction is a command which is given to the computer to perform an operation on a piece of data.

Primary Memory	Secondary memory
It is directly accessed by CPU.	It is not directly accessed by CPU.
The access of memory is done by making use of addresses or data buses.	Here the Memory access is done through the input and output channels.
The Primary memory is embedded with 2 types of technologies. They are RAM and ROM.	The secondary memory are stored in mass storage units like CD ROM, CD, DVD, Floppy disk storage.
Volatile in nature.	Non-Volatile in nature.
Much faster than the secondary Memory.	Slower than the Primary Memory.
Costlier than secondary memory.	Cheaper than the Primary Memory.
It is temporary memory.	Secondary memory is permanent.

Memory enables the computer to store the program. The memory unit is of two types:
(i) Primary memory
(ii) Secondary memory
The primary memory is used to store data temporarily and secondary memory stores the data permanently.

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.

Data Information Data is a collection of facts from which the information may be derived. It is an unprocessed collection of facts in a manner suitable for communication, interpretation or processing. Information is a collection of facts from the conclusions can be drawn. Information is a processed facts, active, Business based and transformed from data. Eg. 134, 16, Kavitha Does not give meaning. Eg. Kavitha is 16 years old.
Conveys meaning.

Computer is an Electronic Machine, capable of performing basic operations like addition, multiplication, division etc. Computer accepts data as input, process it, produce output and stores it for future.