1. Introduction to PHP

PHP (Hypertext Preprocessor) is a server-side scripting language used to create dynamic web pages. It is widely used with HTML and databases like MySQL.

Why Use PHP?

• Runs on all major operating systems (Windows, macOS, Linux).

• Can be embedded into HTML.

• Supports databases like MySQL.

• Open-source and widely supported.

2. Setting Up PHP

To run PHP, you need:

• XAMPP or WAMP (Local Server)

• A text editor (VS Code, Sublime, Notepad++, etc.)

After installing XAMPP/WAMP, start Apache and MySQL, and store your files in the htdocs folder (www for WAMP).

3. Basic PHP Syntax

PHP code is written inside <?php ... ?> tags.

<?php
echo "Hello, World!";
?>

Save this as index.php and open it in your browser ( http://localhost/index.php ).

4. Variables in PHP

<?php
$name = "John";
$age = 25;
echo "My name is $name and I am $age years old.";
?>

• Variables start with $

• Strings use " or '

• Concatenation is done using . (dot)

5. Data Types

PHP supports:

• String ($text = "Hello";)

• Integer ($number = 25;)

• Float ($price = 12.99;)

• Boolean ($isValid = true;)

• Array ($colors = ["Red", "Green", "Blue"];)

6. Conditional Statements

<?php
$age = 20;

if ($age >= 18) {
    echo "You are an adult.";
} else {
    echo "You are a minor.";
}
?>

7. Loops in PHP

For Loop

<?php
for ($i = 1; $i <= 5; $i++) {
    echo "Number: $i <br>";
}
?>

While Loop

<?php
$i = 1;
while ($i <= 5) {
    echo "Number: $i <br>";
    $i++;
}
?>

8. Functions in PHP

<?php
function greet($name) {
    return "Hello, $name!";
}
echo greet("Alice");
?>

9. Forms and User Input

Create an HTML form:

<form method="POST" action="process.php">
    <input type="text" name="username" placeholder="Enter your name">
    <button type="submit">Submit</button>
</form>

Handle it in process.php:

<?php
if ($_SERVER["REQUEST_METHOD"] == "POST") {
    $name = $_POST['username'];
    echo "Welcome, $name!";
}
?>

10. Connecting to a Database (MySQL)

<?php
$conn = new mysqli("localhost", "root", "", "test_db");

if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
}
echo "Connected successfully!";
?>

11. Fetching Data from Database

<?php
$result = $conn->query("SELECT * FROM users");
while ($row = $result->fetch_assoc()) {
    echo "User: " . $row['name'] . "<br>";
}
?>

12. Including External Files

Use include or require to import common files:

<?php include 'header.php'; ?>

Next Steps

Now that you know the basics, try practicing HTML on  https://www.w3schools.com/

If you need further support, feel free to ask here.