PHP: Hypertext Preprocessor 4.0


PHP: Hypertext Preprocessor 4.0, commonly referred to as PHP 4.0, is an open-source scripting language designed for web development. It is embedded into HTML and is primarily used to create dynamic website content. Released in May 2000, PHP 4.0 introduced new features like improved speed and efficiency, session handling and more object-oriented programming.


“Pee Aych Pee: Hypertext Preprocessor Four Point Zero”

Key Takeaways

Three Main Takeaways about PHP: Hypertext Preprocessor 4.0

  1. Significant Improvement: PHP 4.0 brought significant improvements over its predecessor. It included a scripting engine called “Zend Engine” which greatly improved performance, efficiency, and speed of PHP applications.
  2. Object-Oriented Programming: PHP 4.0 introduced a basic level of object-oriented programming (OOP), thus enhancing the functionality of PHP and offering more flexibility to developers. However, it didn’t fully support all the features of OOP like PHP 5 and later versions did.
  3. Session Handling: PHP 4.0 came with better session handling capabilities making it easier for developers to maintain a track of visitor’s information across different pages of the website. This was crucial for creating more user-friendly and dynamic websites.


PHP: Hypertext Preprocessor 4.0, commonly known as PHP 4, represents an important landmark in the development of web technology due to its key enhancements in performance and features. The introduction of PHP 4 in May 2000 demonstrated a significant improvement over the previous version, primarily due to the newly incorporated Zend Engine 1.0 – an open-source scripting engine specifically designed for PHP. PHP 4 provided better support for many databases, HTTP sessions, output buffering, and an array of additional features which made it a robust tool for building complex and large-scale web applications. It offered improved modularity, extensibility and provided an object-oriented programming framework, thereby fostering web development and allowing for the construction of more efficient, secure, and user-friendly websites and web applications.


PHP: Hypertext Preprocessor 4.0, commonly known as PHP, is fundamentally a server-side scripting language designed for web development, but it’s also used as a general-purpose programming language. Its primary purpose is to develop dynamic and interactive websites. It enables the developers to create web pages that can interact with databases, which is essential in making websites more robust, interactive, and dynamic. Moreover, it also plays a crucial role in e-commerce development, with its ability to seamlessly interact with various database languages like MySQL.PHP provides developers with the necessary tools to get server-side processing functionality on web pages. When a user accesses a PHP-based webpage, the server processes the PHP commands and sends the results back to the user’s browser. This server-side functionality allows for more interactive features, such as form submissions, user login systems, dynamic content updates, and more. Another essential feature is its capability in handling forms, i.e., collecting, processing, and utilizing user information, no matter if it’s from text fields, radio buttons, or drop-down menus on an HTML form. This, in turn, makes PHP instrumental in creating more user-friendly, interactive, and functional websites.


1. WordPress: PHP is the main scripting language behind millions of websites built with WordPress – the most popular content management system (CMS) worldwide. WordPress uses PHP to manage and deliver content dynamically, handle user registration, and provide customization options to developers.2. Facebook: The largest and most popular social media platform utilizes PHP for maintaining and operating its servers and databases. When Facebook started, it was written in PHP 4.0 and as it grew bigger, engineers at Facebook created a PHP derivative called “Hack” to allow it to handle billions of users and their data more efficiently.3. MailChimp: This popular email marketing platform uses PHP for creating dynamic content, managing user signups, scheduling email blasts, and tracking statistics. Developers use PHP to integrate MailChimp APIs into different kinds of websites.

Frequently Asked Questions(FAQ)

**Q: What is PHP: Hypertext Preprocessor 4.0?**A: PHP: Hypertext Preprocessor 4.0, usually referred to as PHP 4, is an earlier version of the PHP scripting language. Like its successors, it is mainly used for server-side web development to create dynamic web content.**Q: What are some features of PHP 4.0?**A: PHP 4.0 introduced many new features including improved support for object-oriented programming, the PHP Zend Engine, more extensions, and increased performance compared to previous versions.**Q: What is the PHP Zend Engine?**A: The PHP Zend Engine is the open-source scripting engine that interprets PHP programming language. It was first introduced with PHP 4.0 and has been part of all subsequent versions.**Q: Is PHP 4.0 still supported?**A: No, PHP 4.0 and its updates are no longer supported. The PHP Group ended support for PHP 4 on December 31, 2007. Developers and users are strongly encouraged to upgrade to the latest version of PHP for better security and functionality.**Q: What are the differences between PHP 4.0 and later versions of PHP?**A: Besides performance improvements and new features, newer versions of PHP like PHP 7 and PHP 8 include advanced object-oriented programming support, anonymous functions, namespaces, and improved error handling.**Q: Who uses PHP 4.0, and why?**A: PHP 4.0 was widely used for web development during its life cycle, but its use has significantly declined since support ended in 2007. Some developers might still use PHP 4.0 for legacy systems, but upgrading to a supported version is highly recommended due to security and performance reasons. **Q: Where can I learn more about PHP 4.0?**A: Various online sources and books provide information about PHP 4.0. However, as it’s an outdated version of PHP, it might be more beneficial to learn about the current version of PHP that’s in use today. You can begin your learning at the official PHP website,

Related Tech Terms

  • Scripting Language
  • Web Development
  • Open Source
  • MySQL Database
  • Server-side Processing

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