Skip to content

Demystifying PHP: A Thorough Guide with Code Examples

The Origins of PHP: From Personal Home Page to Popular Platform

Back in 1994, a Danish-Canadian programmer named Rasmus Lerdorf unleashed a simple tool for tracking visitors to his online resume. He called it the Personal Home Page script. Soon after, developers began using that script for their own websites. As usage grew, Lerdorf kept improving the script‘s capabilities.

By 1997, Personal Home Page had evolved into a full web development language capable of dynamic database queries. At that point, the recursive acronym PHP: Hypertext Preprocessor was born.

Over the next decade, PHP exploded in popularity thanks to:

  • Easy integration with common web servers like Apache
  • Support for a wide variety of databases like MySQL, Oracle and SQL Server
  • A large open source community contributing extensions and frameworks
  • Beginner-friendly syntax similar to C, Java, Perl and other languages

Importantly, PHP filled a critical gap in the early web. As online apps became increasingly interactive, traditional languages like C and Perl fell short for rapid web development. PHP adoption closely tracked internet growth itself:

Year        Total Websites      % Using PHP
1994            ~20,000              0.1%   
2000          ~25 million            0.5%
2005          ~100 million           10%  
2010          ~500 million           50%
2020        > 1.7 billion            78%

Today, PHP powers over 78% of all websites, ranging from simple blogs to platforms like Facebook and Wikipedia. Let‘s unpack why this scripting language became so ubiquitous across the web.

How PHP Code Gets Executed

PHP runs primarily as a server-side scripting language. This means PHP code is executed on a web server instead of the client‘s browser.

When a page built with PHP is requested, here is the basic sequence:

  1. A user types a URL into their browser to visit a PHP website
  2. The browser sends this request to the web server hosting the PHP site
  3. The server runs the PHP processor which executes the PHP code
  4. New HTML markup gets generated from the PHP processing
  5. The server sends this HTML back to the client‘s browser to display

This client-server architecture allows PHP to handle tasks that traditional static HTML cannot. For example:

  • Dynamic content generation: Pull data from a database to customize page content
  • Form validation and processing: Check and sanitize user inputs before inserting into database
  • File and system operations: Read and write files directly on server filesystem

With PHP executing on the server, the client browser simply renders the final HTML markup. This makes website building efficient.

Now let‘s walk through a quick code snippet to demonstrate basic PHP syntax.

Sample PHP Code

<!DOCTYPE html>
<html>

<body>

  <?php

    // PHP logic goes between <?php tags

    // Define and display variables  
    $name = "John Doe";   
    echo "<p>My name is $name</p>";

    // Simple if statement
    if ($name == "John Doe") {
      echo "You entered the correct name!";
    }

  ?>

</body>

</html>

In the above example:

  • <?php ?> tags hold PHP logic that gets executed on the server
  • $name is a variable storing the value "John Doe"
  • echo prints output that gets rendered into the HTML
  • The if statement evaluates a logical test

Keep in mind this is a trivial example. Real-world PHP applications have thousands of lines handling data, interfaces and business logic.

Now let‘s explore some common use cases.

Widespread Use of PHP Across the Web

Websites leveraging PHP range from personal blogs to some of the highest-traffic sites worldwide. The flexibility and scalability of PHP make it well-suited for:

  • Custom CMS solutions: Building tailored content management systems for clients
  • E-commerce platforms: Product catalogs, shopping carts, payment and fulfillment systems
  • Web applications: Data dashboards, travel booking platforms, social networks and more
  • APIs: Providing programmatic data access via REST and SOAP APIs
  • Embedded devices: Some TV set-top boxes, printers and IoT gadgets utilize PHP apps

Popular web frameworks like WordPress, Drupal, Laravel and Symfony are also built with PHP. These frameworks provide pre-built components for faster development.

Let‘s compare PHP to some alternative web languages:

Language Key Strengths Typical Usage
PHP Great for databases, simple syntax, cross-platform CMS, ecommerce, web apps
Python Strong for scripting tasks, machine learning Automation scripts, data science
JavaScript In-browser interactivity, event handling Frontend design, visual effects
Java Strongly-typed, robust for large apps Enterprise backends, Android apps
C# / .NET Powerful Windows development platform Business applications, video games

As you can see, languages have overlapping capabilities but tend to excel in certain areas. PHP strikes a balance between rapid prototyping and large-scale deployment – making it a versatile choice for web projects.

Next let‘s cover some frequently asked questions about PHP:

PHP FAQs

Here are answers to some common questions about PHP:

What does PHP stand for?

Originally PHP stood for Personal Home Page. Currently it stands for the recursive initialism PHP: Hypertext Preprocessor.

Is PHP better than JavaScript?

PHP and JavaScript serve very different but complementary purposes. PHP runs on the server to handle backend logic like databases. JavaScript runs client-side in the browser to control interactivity. Often they work together in full-stack web applications.

Is PHP hard to learn?

PHP has a relatively gentle learning curve compared to languages like C++ or Rust. Those familiar with C-style syntax tend to pick up PHP quickly. You can build real-world apps without grasping advanced computer science concepts.

Is PHP still used in 2023?

Yes, PHP usage remains extremely widespread. It still powers most WordPress sites and custom CMS solutions. Major companies like Facebook also rely heavily on PHP serving millions of dynamic pageviews per day.

What can PHP do that JavaScript cannot?

PHP interfaces better with server-side databases and filesystems. It can execute privileged operating system commands for tasks like uploading files. JavaScript focuses more on client-side UI logic executing within a browser sandbox.

The Future of PHP

Given its long history, you may wonder whether PHP is still relevant moving forward. Some argue that trendier languages like Python or Node.js make PHP obsolete for modern web development.

I contend that core PHP itself still has a bright future due to:

  • New versions adding useful features like typed properties and JIT compilation
  • Major frameworks like Laravel bringing PHP on par with Python and Ruby
  • Billions of live PHP-based websites that businesses rely on for revenue
  • A massive developer ecosystem minimizing risks for PHP over alternative languages
  • Performance continuing to improve to rival other scripting languages

However, PHP growth may slow as companies transition traditional websites into web apps with JavaScript-heavy stacks. Still, I predict PHP will remain relevant for decades powering CMS, ecommerce, APIs and legacy systems.

Performance Benchmarks

PHP 8.1 introduced a just-in-time (JIT) compiler to significantly improve processing efficiency:

Operation              PHP 8.0 (sec)   PHP 8.1 (sec)   Improvement 
String Concatenation       2.10             1.30          38% faster   
Array Summation         0.075          0.070            7% faster
JSON Encoding            0.12           0.096           20% faster    

Smaller times are better for the benchmarks above

So while PHP is adding cutting-edge performance gains, JavaScript runtimes like Node.js are doing the same. Ultimately web architecture decisions depend on application needs rather than language micro-benchmarks.

Conclusion

I hope this guide gave you a thorough look at PHP and its capabilities. To quickly recap:

  • PHP started off as Rasmus Lerdorf‘s Personal Home Page script
  • It evolved into a versatile server-side language powering over 3/4 of all websites
  • PHP code gets executed on the server to generate dynamic HTML
  • It performs well for tasks like database interactions and file I/O
  • PHP has a large ecosystem of frameworks and developer support

With approachable syntax and widespread usage, PHP remains an optimal choice for all kinds of web projects in 2023 and beyond. It may no longer be the trendiest kid on the block, but PHP continues adding features matching modern coding paradigms.

For creating content-heavy sites like blogs and catalogs, I still recommend PHP as a robust server-side language. Give it a try yourself to build fast and functional web applications.