PHP variables are used to store values and information. Variables must start with a $ sign and can be of different data types including integers, floats, strings, arrays and objects. PHP is a loosely typed language so variables do not need to be declared and their type is determined by the value. Examples show how to assign values to variables, perform operations on them, get string lengths and positions, and demonstrate variable scoping using the $$ syntax.

1. Variables in PHP
Introduction
A variable is a thing which is used to store the value or information. The value or
information can be text, number, string, and array. In PHP variables are assigned with $
sign. It used before assigning variables in PHP. If you do not use a $ sign before assigning
the variables then they will not work. All variables in PHP are prefixed with a dollar sign. The
dollar sign is not technically part of the variable name, but it is required as the first
character for the PHP variables. The syntax of declaring the variable in PHP following is:
$variable=value;
e.g.:- $name="Vineet";
$num= 40;
Rules for Declaring Variables
 PHP variables must start with (dollar) $ sign.
 PHP variable name must start with a letter or an underscore "_". e.g.:- $variable or
$_variable.
 PHP variable name can only contain alpha-numeric characters and underscores.
 PHP variable name should not contain spaces.
 PHP variables more than one word can also be distinguished with capitalization.
e.g.:-$variable Name.
 PHP variables more than one word should be separated with underscore. e.g.:-
$variable_name.
Types of variables in PHP
PHP variables can have different types which are as follows:
 Booleans :- That takes two values TRUE or FALSE.
 integers:- Integers are {...,-2,-1,0,1,2,...}.
 floating point numbers:- It is also called "doubles" or "real numbers". which
represent numbers with decimals.
 strings:- Strings are set of characters.
 arrays:- Array is also a variable but array can store more than one value or
information.
 objects:- Objects are user-defined.
 resources:- Resource variables are created by special PHP functions.
PHP is Loosely Type Language
PHP is loosely typed language because there is no need for type casting; i.e. there is no
need to declare (define) the type and name of the variable before using it. PHP
automatically converts the variable to the correct data type, depending on its value. While
in a strongly typed programming language you need type casting i.e. you have to declare
(define) the type and name of the variable before using it.
www.vineetsaini.wordpress.com

2. Some examples of variables in PHP
1. In the following example we declare a variable with the name var and the value of var is
10.
<?php
$var=10;
echo $var;
?>
Output
2. If you want to add two values then you can add them. In the following example you will
see how to add two values in PHP.
<?php
$var1=10;
$var2=20;
$sum=$var1+$var2;
echo "The sum of 10 and 20 is : ",$sum;
?>
Output
www.vineetsaini.wordpress.com

3. 3. In the following example we declare a name variable and the value assigned to the
name variable is "Vineet Saini". This is a string example.
<?php
$name="Vineet Saini";
echo $name;
?>
Output
4. If you want to add two strings i.e. first name and last name then you will use the dot (.)
operator. The Dot (.) operator is used to add two strings i.e. concatenate two strings.
Which is shown in the following image.
<?php
$firstname="Vineet";
$lastname="Saini";
echo "The full Name is : " .$firstname." ".$lastname;
?>
www.vineetsaini.wordpress.com

4. Output
5. If you want to find the length of your name or any string then you will use the strlen()
function. For the new line you will use <br> . Such as in the following image.
<?php
$firstname="Vineet";
$lastname="Saini";
$fullname=$firstname." ".$lastname;
echo "The full Name is : " .$fullname.'<br>';
echo "The length of fullname is : ";
echo strlen($fullname);
?>
Output
6. If you want to find the position of any text/character in a string then you will use the
strpos() function. In the following example we find the position of "Saini" text in the
www.vineetsaini.wordpress.com

5. fullname string. Such as in the following image.
<?php
$firstname="Vineet";
$lastname="Saini";
$fullname=$firstname." ".$lastname;
echo "The full Name is : " .$fullname.'<br>';
echo "The position of your text/character is : ";
echo strpos($fullname,"Saini");
?>
Output
7. In PHP the syntax $name and $$name can be very confusing. But I tell you $name is a
variable and $$name is a variable of a variable. A variable of a variable allows us to change
the name of a variable dynamically.
<?php
$name="Vineet";
$Vineet="Saini";
echo $name.'<br>';
echo $$name;
?>
Output
www.vineetsaini.wordpress.com

6. Conclusion
So in this article you saw, how to use of variables in PHP. Using this article you can easily
understand variables in PHP. This article is very useful for PHP beginners.
www.vineetsaini.wordpress.com