Introduction

PHP is one of the most popular server-side programming languages used to create dynamic websites and web applications. Before learning advanced topics, every beginner should understand echo statements, variables, comments, data types, and operators.

1. Echo in PHP

The echo statement prints output to the browser.

<?php
echo "Hello World!";
echo "<br>";
echo "Welcome to PHP!";
?>

2. Variables

Variables store information and always start with the $ symbol.

<?php
$name = "Harsh";
$age = 22;

echo $name;
echo "<br>";
echo $age;
?>

3. Comments

Comments help explain code and are ignored during execution.

// Single-line comment

# Another single-line comment

/*
Multi-line
Comment
*/

4. Data Types

Data Type	Description	Example
String	Stores text	"Harsh"
Integer	Stores whole numbers	22
Float	Stores decimal numbers	99.99
Boolean	Stores true or false	true / false

String Example

<?php
$name = "Harsh";
echo $name;
?>

Integer Example

<?php
$age = 22;
echo $age;
?>

Float Example

<?php
$price = 99.95;
echo $price;
?>

Boolean Example

<?php
$isLoggedIn = true;

if($isLoggedIn){
    echo "User Logged In";
}
?>

5. Arithmetic Operators

Operator	Meaning	Example
+	Addition	10 + 5
-	Subtraction	10 - 5
*	Multiplication	10 * 5
/	Division	10 / 5
%	Modulus	10 % 3

<?php
$a = 10;
$b = 3;

echo $a + $b;
echo "<br>";

echo $a - $b;
echo "<br>";

echo $a * $b;
echo "<br>";

echo $a / $b;
echo "<br>";

echo $a % $b;
?>

6. Comparison Operators

Operator	Meaning
==	Equal To
===	Equal Value & Type
!=	Not Equal
!==	Not Equal Value or Type
>	Greater Than
<	Less Than
>=	Greater Than or Equal
<=	Less Than or Equal

<?php
$x = 10;
$y = 20;

var_dump($x < $y);
var_dump($x == $y);
var_dump($x != $y);
?>

7. Logical Operators

Operator	Meaning
&&	AND - Both conditions must be true
||	OR - At least one condition must be true
!	NOT - Reverses the result

<?php

$age = 20;
$citizen = true;

if($age >= 18 && $citizen){
    echo "Eligible";
}

$isAdmin = false;

if(!$isAdmin){
    echo " Access Denied";
}

?>

8. Complete PHP Example

<?php

$name = "Harsh";
$age = 22;
$salary = 50000.50;
$isStudent = true;

echo "Name: " . $name;
echo "<br>";

echo "Age: " . $age;
echo "<br>";

echo "Salary: " . $salary;
echo "<br>";

echo "Student: " . ($isStudent ? "Yes" : "No");

?>

Conclusion

Echo, variables, comments, data types, and operators are the building blocks of PHP programming. Once you understand these concepts, you can easily move on to conditions, loops, functions, arrays, forms, sessions, and database development.