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7 Mar, 2014 11:47 am PST

How to declare Variables in php?

How to declare Variables in php?


As name suggest, an entity who`s value can be changed. During processing u need to process data, so this data is stored in memory with the help of variable. A variable is a keyword or phrase that acts as an identifier for a value stored in a system’s memory The declaration preceded by ‘$’(dollar) sign followed by variable name with leaving any blank space in between.

Syntax: -

$Variable_Name; or

$variable_Name= Value ;




$name=”hello world”;





// to add, subtract, multiply, divide two numbers and display the result


$num1 =15;

$num2 =20;

$result = $num1 + $num2 ;

echo ’ <h2 > ’; // html tags


echo ’ Addtion of ’. $num1 . ’ and ’. $num2 . ’ is ’. $result ;

operator is used to print value of .( Dot ) variable←


echo ’ <br > ’;

$num1 =105.655;

$num2 =158.8594;

$result = $num1 - $num2 ;

echo ’ Subtraction of ’. $num1 . ’ and ’. $num2 . ’ is ’. $result ;

echo ’ <br > ’;

$num1 = -105;

$num2 =158.8594;

$result = $num1 * $num2 ;

echo " Multiplication of { $num1 } and { $num2 } is { $result } " ; // different way printing values



echo ’ <br > ’;

$num1 =105;

$num2 =0.5;

$result = $num1 / $num2 ;

echo ’ Division of ’. $num1 . ’ and ’. $num2 . ’ is ’. $result ;






Attachment: Variable.php

How to declare variable in PHP


Variables are capable to store information in them.In PHP all the variables begin with a dollar sign "$".It can store values like string,integer,boolean etc.

There is no need to declare data type before adding a value to it.A variable is created at the same moment you provide it a value,there is no function or method to declare a variable

When creating and declaring a variable certain rules are to be followed:

    »Variable must start with letter or underscore(_).

     »Variable with more than one word should be separated by underscore(_).

     »PHP variables are case sensitive.

     »It can have numeric(0-9), letter(a-z, A-Z) or underscore"_"

//Declaring variable in PHP

<!DOCTYPE html>







echo $str;

echo "<br>"."Value of a = ",$a;

echo "<br>"."Value of b = ",$b


echo "<br>"."Value of c = ",$c;




/*Output of the above program is:

 WELCOME TO PHP PROGRAMMING!Value of a = 12Value of b = 8.2Value of c = 20.2


Attachment: Variable.php
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