"I am Saqib Jahangir. A passionate vlogger, software engineer, trainer and avid traveler with a deep love for exploring the hidden gems of our beautiful planet. With a strong foundation in Application Development, Application Architecture & Database Design and Product Management, I bring over a decade of hands-on experience building secure, scalable, and resilient web applications for a diverse range of industries."


Click Above to BOOK HOTEL NOW!

Variables and Data Types

 

Introduction

Variables in PHP are used to store data that can be used and manipulated throughout your script. PHP is a loosely typed language, which means you do not need to declare the type of a variable explicitly. The data type is determined automatically based on the value assigned.

Variables

A variable in PHP always starts with a dollar sign $ followed by the variable name. Variable names are case-sensitive and must start with a letter or underscore.

Example:

<?php

$name = "Alice";

$age = 25;

$isAdmin = true;

?>

Data Types

PHP supports several data types. The most common ones include:

String – Represents text.

<?php

$greeting = "Hello, World!";

?>

Integer – Whole numbers without decimals.

<?php

$year = 2025;

?>

Float (or Double) – Numbers with decimals.

<?php

$price = 19.99;

?>

Boolean – Represents true or false.

<?php

$isLoggedIn = true;

?>

Array – Stores multiple values in a single variable.

<?php

$colors = ["Red", "Green", "Blue"];

?>

Object – Represents an instance of a class.

<?php

$date = new DateTime();

?>

Null – Represents a variable with no value.

<?php

$middleName = null;

?>

Dynamic Typing

Since PHP is loosely typed, you can change the type of a variable by assigning a new value of a different type:

<?php

$var = 10;       // integer

$var = "Ten";    // now a string

?>

 

Click Below to Shop Now at AMAZON

Click Below to Shop Now at AMAZON

Popular Posts

Operators (Arithmetic, Comparison, Logical)

  Operators in PHP are symbols that perform operations on variables and values. They are essential for performing calculations, comparing values, and making logical decisions in your code. PHP supports several types of operators, including arithmetic, comparison, and logical operators. Arithmetic Operators Arithmetic operators are used to perform basic mathematical operations. Example: <?php $a = 10; $b = 3;   echo $a + $b; // 13 echo $a - $b; // 7 echo $a * $b; // 30 echo $a / $b; // 3.3333 echo $a % $b; // 1 (modulus) echo $a ** $b; // 1000 (exponentiation) ?> Comparison Operators Comparison operators are used to compare two values. They return true or false . Example: <?php $x = 5; $y = 10;   var_dump($x == $y);   // false var_dump($x != $y);   // true var_dump($x === $y); // false (checks value and type) var_dump($x !== $y); // true var_dump($x > $y);    // false var_dum...
Read more

Functions (Built-in & User-defined)

  Functions in PHP are blocks of code designed to perform a specific task. They help make code reusable, organized, and easier to maintain. PHP provides built-in functions for common tasks, and also allows you to create your own user-defined functions . Built-in Functions PHP has hundreds of built-in functions that perform predefined operations such as string manipulation, mathematical calculations, and array handling. Example (Built-in Functions): <?php // String length echo strlen("Hello World"); // Outputs: 11   // Find maximum value in an array echo max(10, 20, 30); // Outputs: 30   // Convert string to uppercase echo strtoupper("php is awesome"); // Outputs: PHP IS AWESOME ?> User-defined Functions You can create your own functions to execute code whenever needed. This helps reduce repetition and makes programs easier to read. Syntax: function functionName($parameter1, $parameter2) {     // Code to...
Read more