A Note for Intermediate-Advanced Developers

If you are already well versed with PHP then you should read https://phptherightway.com/ this is just a 1-2 hours read.

Introduction

PHP is a very polarizing language. Some people love it, some people hate it. If we move one step above the emotions and we look at the language as a tool, PHP has a lot to offer.

PHP is a programming language mostly used to create Web Applications.

<aside> 💡 PHP isn’t dead and as a matter of fact Facebook, Wikipedia, Slack, Etsy all use some PHP.

</aside>

PHP is often called a “scripting language” and it’s an interpreted language.

• The PHP interpreter is responsible for interpreting the instructions written in a PHP program when it’s executed.

PHP is a dynamically typed language.

• The types of variables are checked at runtime, rather than before the code is executed as it happens for statically typed languages (which also happen to be compiled, the two characteristics often go hand in hand).

PHP is also loosely (weakly) typed so you don’t need to declare the types of your variables.

Being interpreted, loosely and dynamically typed will make bugs harder to find before they happen at runtime. But on the other hand, an interpreted language has more flexibility.

<aside> 💡 PHP is written, internally, in C.

</aside>

PHP supports object-oriented programming, and also functional programming.

• It has evolved dramatically over the years, notably adding a solid object-oriented model in PHP 5.0 (2004), anonymous functions and namespaces in PHP 5.3 (2009), and traits in PHP 5.4 (2012).

The PHP file has a <?php opening, which says “here starts some PHP code”, an ending ?> that closes the PHP code snippet, and inside it the PHP code.

• We have this opening/closing structure because we can embed HTML and CSS inside PHP file.
• The ending tag is not required when the file contains purely PHP code.

PHP is a server-side language and it is typically used in 2 ways.

• One is within an HTML page, so PHP is used to “add” stuff to the HTML which is manually defined in the .php file.
  • PHP is a scripting language, whose goal is to be able to “decorate” an HTML page with dynamic data.
  • A PHP page is technically an HTML page, the browser can figure out how to display that in the window.