A company can be called E-Business if and only if
(i) It has the ability to conduct business electronically over the Internet.
(ii) It manages payment transaction through the Internet.
(iii) It has a platform for selling products & services via the Internet.

(i) A segment is a three-character alphanumeric code.
(ii) These segments are listed in segment tables .
(iii) Segments may contain one, or several related user data elements.

(i) Multimedia is available in many public places like trade shows, libraries, railway stations, museums, malls, airports, banks, hotels and exhibitions in the form of kiosks.
(ii) The information presented in kiosk are enriched with animation, video, still pictures, graphics, diagrams, maps, audio and text. Banks uses kiosks in the form of ATM machines.

< ?php
＄x = 1;
while(＄x < = 10)
{
echo sx:
＄x++;
}
? >

(i) E-Banking plays an important role in our day today life, via Internet it can be accessed anytime, anywhere 24/7.
(ii) The speed and efficiency was very much better than that of done by counter at bank.
(iii) Owaday's online payment were done via Internet to avoid standing in the queue at office to paybills with very low transaction fees.

(i) HTTP: A protocol used between a web client and a web server protects non-secure data transmissions. The core protocol of the World Wide Web.
(ii) HTTPS: A protocol used between a web client and a web server permits secure data transmissions.
(iii) FTP: Used between computers for sending and receiving data. Enables a client to send and receive complete files from a server.

User defined Functions	System define Functions
(i) Functions are provided by the user. (ie) we can create own functions.	(i) Built-in function are functions that exist in PHP installation package.
(ii) Example function insertMsg() { echo "Helo world" } insertMsg();	(ii) Example rename_function()

In ER Model, relationship exists between two entities. Three types of relationships are available and the Entity-Relationship (ER) diagram is based on the three types listed below
(i) One-to-One relationship: Consider two entities A and B. One-to-one (1:1) relationship is said to exist in a relational database design, if 0 or 1 instance of entity A is associated with 0 or 1 instance of entity B, and 0 or 1 instance of entity B is associated with 0 or I instance of entity A.
(ii) One-to-Many relationship: Consider two entities A and B. One-to-many (1:N) relationship is said to exist in a relational database design, for 1 instance of entity A there exists 0 or 1 or many instances of entity B, but for 1 instance of entity B there exists 0 ur 1 instance of entity A.
(iii) Many-to-Many relationship: Consider two entities A and B. many-to-many (M:N) relationship is said to exist in a relational database design, for 1 instance of entity A there exists 0 or 1 or many instances of entity B, and for 1 instance of entity B there exists 0 or 1 or many instance of entity A.

(i) Any text (or) object that you place on the master page will appear on the entire document pages to which the master is applied.
(ii) It shortens the amount of time because you don't have to create the same objects repeatedly on subsequent pages.
(iii) Master pages commonly contain repeating logos, page numbers, headers and footers.
(iv) They also contain non-printing layout guides, such as column guides, ruler guides and margin guides.

1. Credit card number: The modern credit card number has 16-digit unique identification number.
2. The first digit of the credit card number is Major Industry Identifier (MII).
i) It identifies the issuer category.
ii) e.g. 1 - Airlines,4 - Banks
3. The next 5 digits uniquely identify the issuing organization
4. The first 6 digits together called as Issuer Identifier number (IlN) or Bank Identification number (BIN).
5. The next 9 digits are the account number.
6. The last digit is a check digit (based to the Luhn algorithm).

(i) To avoid the major disadvantage of Flat namespace, hierarchical namespace is used in large
(ii)  Hierarchical namespace is where the name is made up of several parts.
a. First part may represent the nature of the organization.
b. Second part may represent the name of the organization, and
c. Third part may represent the department of the organization and so on.
(iii) In this way the power to control the namespace can be decentralized.
(iv) The centralized authority can be given to nature and then to the name of the organization and so on.
(v) To achieve hierarchical namespace, Domain Name Space was designed.

The Internet Explosion
(i) Internet is simply defined as the World Wide Web connection of individual networks which operated by academic, industry, government, and private parties.
(ii)  The Internet served to interconnect with laboratories engaged at government research, and from 1994 it is expanded to serve millions of user and a multiple purpose in all parts of this universe.
(iii) In few years, the Internet built itself as a highly powerful platform that changed their way we do business and the way we communicate. Internet promotes as the universal source of information of billions of people, at work, at home, at school. Internet gave high communication medium, has given an international, "Globalised" at all dimension of the world.
(iv) Internet is growing all the time. By two things, have marked its evolution nowadays the mobile technology and social web. These two innovations have been changed the people life style to use Internet. We may find many communities in social web. Facebook was created in 2004 but gowned into world wide network all over more than 2,230 million active users.
(v) Mobile technology on hand made possible to great reach of Internet and increase the Internet user all over the world.
(vi) The Internet allows all to be democratic in mass media. Anyone can have a webpage in
(vii) Internet with very low investment. Similarly any business can reach a very large market directly, economically and fast, no matter of location or size of their business. Almost anyone that who san read and write can have a access and a presence in World Wide Web with very low investment. People everywhere can express and publish their ideas and opinions via blogging.

Symmetric Key Encryption	Asymmetric Key Encryption
Same key is used for both encryption and decryption	Different keys are used for encryption and decryption
Speed of encryption or decryption is very fast	Speed of encryption or decryption is comparatively slow
Plain text and cipher text are of same size	The size of cipher text is always greater than plain text.
Algorithms like DES, AES, RC4 uses symmetric key encryption	Algorithms like RSA, ECC, DSA use asymmetric key encryption
Provides confidentiality	Provides confidentiality, authenticity and non-repudiation
The number of key used grows exponentially with the number of users	The number of key used grows linearly with the number of users

OSS projects are collaboration opportunities that improve skills and build connections in the field.
Domains that developers can contribute to the open source community include:
1. Communication tools.
2. Distributed revision control systems.
3. Bug trackers and task lists.
4. Testing and debugging tools.
(i) There are many open source softwares. So, we can select and use any software that suits our needs.
(ii) The complete options of the software can be used without any cost and restrictions.
(iii) We can share our ideas with the team. write the required code and share it with many.
(iv) As we can identify the programming techniques of group members, we can learn many ideas and make our program writing skills more efficient.
(v) The coding in open source software are being groomed by many enthusiastical members of the groups. So, if we report problems that we have in the program they are quickly mended by the group's effort.
(vi) As we can make changes to the open source software, we can add the most required features in the software.
(vii) Many open source software are very user friendly.
 

No.	TCP/IP	OSI
1.	It is client server model. ie. when the client requests for service it is provided by the server.	It is conceptual model.
2.	It is standard protocol used for every network including the internet.	It is not a protocol but a reference model used for understanding and designing the system architecture.
3.	It is four layered model.	It has seven layers.
4.	TCP / IP follows vertical approach.	OSI model supports horizontal approach.
5.	It is Tangible	It is not Tangible
6.	It is follows top to bottom approach	It is follows a bottom-up approach

Error handling is the process of catching errors raised by our program and then taking appropriate action.
Different error handling methods are
Simple "die ()" statements;
Custom error and error triggers;
Error reporting.
(i) Using the die () function:-
Example:
$file = fopen("Welcome.txt", "r");
?>
Above example shows a simple script that opens a text file. If the file does not exists you might get an error like this.
Warning:
fopen (welcome.txt) [function.fopen]: failed to open stream: No such file or directory in
C:\webfolder\test.php on line 2
To prevent the user from getting an error message like the one above, test whether the file before we
try to access it.
if (!file_exists ("welcome.txt"))
{
die ("File not found");
} else
{
file = fopen ("Welcome.txt", "r");
}
Now if the file does not exists you get an error like this
File not found
The code above is more efficient than the earlier code, because it uses a simple error handling mechanism to stop the script after the error.
However, simply stopping the script is not always the right way to go. Let's take a look at alternative php functions for handling errors.
(ii) Creating a custom Error Handler
Creating a custom error handler is quite simple. Simply create a special function that can be called when an error occurs in PHP.
This function must be able to handle a minimum of two parameters (error level and error message) but can accept up to five parameters.
Syntax:
error_function (error_level, error_message, error_file, error_line, error_context)
(iii) Error report levels:
These error report levels are the different types of error the user defined error handler can be used for:
E_WARNING, E_NOTICE, E_USER_ERROR, E_USER_WARNING, E_USER_NOTICE,... etc.
Set Error Handler:
The default error handling for PHP is the built-in error handle;
Example:
To use our custom error handle for all errors:
set_error_handler("Custom Error");

Looping structure are useful for writing iteration logics. It is the most important feature of many programming languages including PHP.
Looping categories are
(i) for loop
(ii) for each loop
(iii) while loop
(iv) Do while loop
(i) for loop:
It is used for iteration logics when the programmer know in advance how many times the loop should run.
Syntax:
for (init counter; test counter; increment counter)
{
code to be executed;
}
Parameters:
init counter: To initialize the loop initial counter value
test counter : Evaluated for every iteration, of the loop.
If it evaluates to TRUE, the loop continues.
If it evaluates to FALSE, the loops ends.
Increment counter:Increases the loop counter value.

(ii) for each loop:
It works only with arrays.
Loop iteration depends on each KEY value pair in the Array.
In loop iteration, value of the current array element is assigned to $value variable and the array
pointer is shifted by one until it reaches the end of the array element.
Syntax:
for each ($array as $value)
{
code to be executed;
}
(iii) While loop:
It is used for simple iteration logics.
It checks the condition, if the condition is true, and it executes the loop.
Syntax:
while (condition is true)
code to be executed;
}
(iv) Do while loop:
Do while loop always run the statement inside the loop block at the first time of execution. It then checks the condition. If the specified condition is true, it executes the loop.
Syntax:
do
{
code to be executed;
}while (condition is true);
}

Indexed array:
An indexed array is an array that uses a numeric index to access its elements. The index is a number that starts at 0 for the first element and increases by 1 for each subsequent element.
We can create an indexed array in PHP,
(i) by enclosing a comma-separated list of values in square brackets (or)
(ii) by using the array() function.
Syntax
$array Variable=[element1, element2, element 3, ... elementN];
(or)
$arrayVariable array( element1, element2, element3.... elementN);
Examples
(a) $fruits = ['apple, "banana, 'orange'];
(b) $fruits = array('apple, "banana, 'orange');



Associative array
An associative array is a data structure that store a collection of key-value pairs. The keys are used to identify the values, and the values can be of any data type. The keys in an associative array are often called "labels" because they label or identify the corresponding values.
We can create an associative array in PHP,
(i) by enclosing a comma-separated list of key-value pairs in square brackets (or) 
(ii) by using the array() function.
Syntax

$arrayVariable [ "key1" => "value1", "key2"=>"value2", "key3"=>"value3" "key N=> "valueN" ];

Example
$student [
"Name" => "Ram",
"Age" => 25,
"Place" => "Trichy"
];

Tool	Tool Toolbox	Cursor	Use
Pointer tool			Used to select, move, and resize text objects and graphics.
Text tool			Used to type, select, and edit text.
Rotating tool			Used to select and rotate objects
Cropping tool			Used to trim imported graphics
Line tool			Used to draw straight lines in any direction
Constrained line Tool			Used to draw vertical or horizontal lines
Rectangle tool			Used to draw squares and rectangles
Rectangle frame tool			Used to create rectangular place holders for text and graphics
Ellipse tool			Used to draw circles and ellipses
Ellipse frame tool			Used to create elliptical place holders for text and graphics
Polygon tool			Used to draw polygons
Polygon frame tool			Used to create polygonal place holders for text and graphics
Hand tool			Used to scroll the page (an alternative to the scroll bar)
Zoom tool			Used to magnify or reduce an area of the page.

(i) It is the subset of message. A segment is a three - character alphanumeric code.
(ii) These segments are listed in segment tables.
(iii) Segments may contain one, or several related user data elements

Merchant's-electronic device that enables the e - payments. It reads the card information from EMV or magnetic strip

i) Static text, the text or the words will remain static as a heading or in a line, or in a paragraph. The words are given along with the images to explain about the images.
ii) In static text the words will either give information or support an image or video.

Switch statements work the same as if statements but they can check for multiple values at a time

INSERT, SELECT,UPDATE and DELETE.

A significant output of simulation is the trace files. Trace files can document every incident that happened in the simulation and are used for examination.

A set of computers connected together for the purpose of sharing resources is called as computer network.

If Statement	If else Statement
if statement executes some code if one condition is true.	If statement executes some code if the condition is true and else part of code executes if the condition is false.