Variable declaration with dollar sign in PHP

Introduction

In PHP, every variable starts with a dollar sign ($). This helps the computer know you are using a variable.

When you want to store a number or text to use later.

When you need to remember a user's name or age.

When you want to keep track of a score in a game.

When you want to save a result from a calculation.

When you want to change the value and use it again.

Syntax

PHP

$variable_name = value;

The dollar sign ($) must come before the variable name.

Variable names can have letters, numbers, and underscores but cannot start with a number.

Examples

This creates a variable called $name and stores the text "Alice" in it.

PHP

$name = "Alice";

This creates a variable called $age and stores the number 25.

PHP

$age = 25;

This creates a variable called $score and starts it at zero.

PHP

$score = 0;

Sample Program

This program creates two variables, $name and $age, then uses them inside a greeting message. It prints the message to the screen.

PHP

<?php
$name = "Bob";
$age = 30;
$greeting = "Hello, $name! You are $age years old.";
echo $greeting;
?>

Important Notes

Always start variable names with a letter or underscore, never a number.

Variable names are case-sensitive: $Name and $name are different.

You can change the value of a variable anytime by assigning a new value.

Summary

All PHP variables start with a dollar sign ($).

Variable names store data like text or numbers.

Use variables to keep and reuse information in your program.