Chapter 1: Introduction to PHP: Getting Started with Server-Side Scripting

In this chapter, we will explore the basics of PHP and get started with server-side scripting. We will cover setting up the PHP development environment, understanding the PHP syntax and structure, and executing PHP code in a web server environment.

1.1 What is PHP and its role in web development:

PHP (Hypertext Preprocessor) is a server-side scripting language used for web development.

It is embedded within HTML and executed on the server before the HTML is sent to the client's browser.

PHP enables dynamic content generation, database connectivity, and interaction with web forms.

1.2 Setting up the PHP development environment:

Install PHP on your local machine or set up a remote PHP environment.

Use an integrated development environment (IDE) or a simple text editor for writing PHP code.

Configure a web server (such as Apache) to interpret PHP files.

Test the PHP installation and server configuration by running a simple "Hello, World!" script.

Example:

php

""

<?php

   echo "Hello, World!";

?>

1.3 Understanding the PHP syntax and structure:

PHP code is enclosed within <?php and ?> tags to differentiate it from HTML.

PHP statements end with a semicolon (;).

Variables are preceded by a dollar sign ($).

Comments can be added using // for single-line comments or /* */ for multi-line comments.

Example:

php

""

<?php

   // This is a single-line comment

   /* This is

      a multi-line comment */

      

   $name = "John Doe"; // Declaring and assigning a value to a variable

   echo "Hello, " . $name . "!"; // Concatenating strings and variable value

?>

1.4 Executing PHP code in a web server environment:

Create a PHP file with a .php extension and place it in the web server's document root.

Access the PHP file through a web browser by entering the file's URL.

The PHP code within the file will be processed by the server, and the resulting output will be displayed in the browser.

Example:

Create a file named "greeting.php" with the following code:

php

""

<?php

   $name = "John Doe";

   echo "Hello, " . $name . "!";

?>

Access the file through a web browser by entering the URL: http://localhost/greeting.php

The browser will display: Hello, John Doe!

This example demonstrates a basic PHP script that declares a variable $name and uses the echo statement to output a personalized greeting.

By following the explanations and examples in this chapter, you will have a solid foundation in understanding PHP and getting started with server-side scripting.