Variables are used for storing the data like strings, numbers , arrays etc in programs.
In PHP a variable starts with a $ sign. Forgetting to add $ sign is a very common mistake for the beginners.
Example for a PHP variable : $variable
And the declaration will look like $variable = VALUE ;
A PHP variable name can start with a letter or underscore ( _ ) symbol and it shouldn’t contain any space or other special characters like *, % , # etc.
See the valid and invalid variable names
- $employee name ( Invalid variable )
- $employee_name ( Valid variable )
There is no type declaration is needed in PHP variable declaration.variable will automatically converted to the type of assigned value to the variable.
For example :
- $variable = 10 ; ( Here $variable will treat as integer automatically, we dont need to specify type as Integer at the declaration command )
- $variable = “I love you”; ( Here $variable will treat as a string automatically, we dont need to specify type as string at the declaration command )
PHP Sample program with variable declaration
<?php $variable_age = 30; $variable_name= "Syam"; $variable_desp="has aged"; echo $variable_name." ". $variable_desp." ".$variable_age; ?>
The result will be look ke
Syam has aged 30
Automatic type conversion is one of the main advantage and feature of PHP programming.