What is PHP?

PHP (Hypertext Preprocessor) is a programming language used mostly for web development. It is a popular option for developing dynamic web pages and online apps and may be incorporated into HTML code to generate dynamic web content. The server will execute PHP scripts to generate HTML output, which is subsequently delivered to the client's web browser for display.

PHP History 

Rasmus Lerdorf invented PHP in 1994 as a collection of Common Gateway Interface (CGI) scripts for monitoring visits to his website. He termed it PHP Tools or Personal Home Page Tools. Over time, additional developers added features and functionality to the project, and in 1997, Andi Gutmans and Zeev Suraski redesigned the language's core, releasing PHP 3 as an open-source effort.

PHP quickly rose to prominence as one of the most popular server-side programming languages for web development. PHP 4 was introduced in 2000 with substantial performance and language enhancements, while PHP 5 was published in 2004 with enhanced object-oriented programming capabilities.

Today, PHP is still extensively used, and a vast community of developers contributes to its continuing maintenance and development. The latest PHP version is 8.2 that was released on November 24, 2022.

Why PHP?

PHP is a popular web development language for various reasons. Primarily, it is reasonably simple to learn, with a clean syntax that makes it accessible to developers of all experience levels. In addition, PHP is supported by the majority of web servers. It is compatible with most operating systems, making it an adaptable alternative for developers working on a variety of projects.

PHP is also renowned for its integration capabilities, which enable programmers to quickly link PHP programs to other technologies, such as databases and web servers, to construct dynamic and interactive online applications. Moreover, because PHP is an open-source language, it is free to use and backed by a vast community of developers continually striving to improve and upgrade it, making it a dependable and well-supported web development alternative.

In addition, PHP has a huge and active developer community, so there are lots of tools and assistance to help you learn the language and debug any problems you may experience. PHP may be utilized for various purposes, including web development and command-line programming. For these reasons, PHP remains a popular choice among developers who wish to create a dynamic and resilient page.

What Does a PHP Developer Do? 

A PHP developer is responsible for designing, developing, and maintaining online a page built with PHP. Typically, they collaborate with developers, designers, and project managers to produce online PHP applications that fulfill their customers' or organizations' demands.

Writing a clean, maintainable, and efficient PHP script, designing server-side applications, and integrating the application with front-end technologies are typical tasks of a PHP developer. During the development phase, they could also troubleshoot and debug.

PHP engineers often have a solid grasp of web development technologies, including HTML, CSS, and JavaScript, as well as knowledge of PHP frameworks like Laravel and Symfony. They may also have expertise in dealing with APIs and third-party services.

In addition to technical expertise, PHP programmers must possess good problem-solving, communication, and teamwork abilities to be part of an efficient PHP development team. They must be detail-oriented, able to work under pressure and tight deadlines, and dedicated to being current with recent web development trends and technology.

How to Become a PHP Developer? 

The following are the general stages of becoming a PHP developer:

Master the Fundamentals of Web Development

Before diving into PHP programming, you should have a good foundation in web development principles and technologies, such as HTML, CSS, and JavaScript.

Learn PHP

After acquiring a foundational grasp of web programming, you can begin to learn PHP. Several online tools and courses are available to assist you in learning PHP and getting started, such as the official PHP manual.

As with any programming language, coding practice is the best approach to become skilled with PHP. Start with modest projects and progress to more complicated applications over time.

Understand the PHP Framework

PHP frameworks like Laravel and Symfony may make PHP development more rapid and effective. Additionally, learning a PHP framework might facilitate collaboration with other developers.

Create a Portfolio

As you gain experience and proficiency in PHP coding, begin to compile a portfolio of your past projects. Personal initiatives and contributions to open-source projects qualify.

Keep Up to Date

The web development landscape is in a perpetual state of change; thus, it is essential to be current with the most recent trends and technology. Attend industry meetings, conferences, and other events to remain current.

Look for Employment Opportunities

Once you feel secure in your PHP programming skills, you should begin your job search. You may search for PHP developer jobs on job boards like Indeed or Glassdoor or connect with recruiters and staffing organizations specializing in tech opportunities.

Advantages of PHP

Here are a few benefits of PHP:

• PHP is an open-source programming language, which implies that it is free for anybody to use and distribute. This renders it an economical option for web development jobs.
• PHP has a large and active developer community, which means there are lots of tools and assistance to help you learn and debug any problems you may experience.
• PHP is compatible with several operating systems, including Windows, Linux, and macOS, and is supported by most web servers, making it a versatile option for developers.
• PHP's basic and uncomplicated syntax makes it simple for beginners to learn, yet complex functionality is available for more experienced developers.
• Because PHP is a server-side scripting language, it enables web applications' rapid and efficient construction.
• PHP may be readily connected with other technologies, such as web servers and databases, to develop a dynamic and interactive online page.
• PHP has a vast library of built-in functions that simplify basic operations such as text manipulation, file processing, and more.
• PHP's built-in security capabilities safeguard online applications from typical security risks, such as SQL injection and cross-site scripting.

PHP is a powerful, widely-used programming language with several benefits, making it a popular option among web developers.

Installation of PHP

The procedure for installing PHP varies based on your operating system and server configuration. Here are some general instructions for installing PHP on a Linux machine using Apache:

Install Apache

If you do not already have a web server, you must install Apache. To install Apache, use the command sudo apt-get install apache2 on Ubuntu.

Install PHP

To install PHP, do sudo apt-get install php on Ubuntu or sudo yum install php on CentOS.

Verify Installation

Once PHP is installed, you may test it by placing PHP files with the extension.php in your web server's document root directory (on Ubuntu, this is normally /var/www/html/). Insert the following PHP code into this file:

<?php
phpinfo();
?>

Save the file and then navigate to http://localhost/info.php in your web browser. If PHP was properly installed, you should see a page containing information about your PHP installation.

Components of PHP

Here are several PHP components:

Core PHP 

Core PHP offers the syntax and fundamental capabilities for developing a page. Variables, PHP arrays, control structures (if/else, switch, loops), functions, classes, and error handling are all included. It also has file management, network programming, and PHP XML parsing capabilities.

Web Server

PHP is intended to be used with a web server such as Apache, Nginx, or IIS. When a user requests a web page from the server, the server forwards the request to PHP, which creates the HTML content that is then returned to the user's browser. PHP can manage incoming user data, such as form submissions, and multiple interfaces with databases and other resources.

// Receiving form data in PHP
if ($_SERVER['REQUEST_METHOD'] == 'POST') {
  $name = $_POST['name'];
  $contact = $_POST['contact'];
  // do something
}

// Sending a response in PHP
echo "Hello World";

Database

PHP is compatible with various database systems, including MySQL, PostgreSQL, Oracle, and Microsoft SQL Server. It has functions and an extension for connecting to databases, running SQL queries, and managing data. This simplifies the storage and retrieval of data for PHP developers.

// Connecting to a MySQL database in PHP
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";
$conn = mysqli_connect($servername, $username, $password, $dbname);

// Executing a MySQL query in PHP
$sql = "SELECT * FROM users WHERE username='khan'";
$res = mysqli_query($conn, $sql);
while ($row = mysqli_fetch_assoc($res)) {
  echo $row['username'];
}

Frameworks

Many prominent PHP frameworks, such as Laravel, Symfony, and CodeIgniter, provide tools and libraries to speed up development and make complicated web applications easier to construct. Routing, authentication, database access, and templating are all characteristics of these frameworks. They also give a consistent framework for organizing PHP code and files. See the following code snippet for an example:

// Routing in Laravel
Route::
get('/user/{id}', function ($id) {
    return 'User '.$id;
})
;

// Authentication in Symfony
if ($this->get('security.authorization_checker')->isGranted('ROLE_USER')) {
  // user is authenticated
}

// Templating in CodeIgniter
$this->load->view('blog', $data);

Content Management System (CMS)

Many prominent CMSs, such as WordPress, Drupal, and Joomla, is written in PHP and offer a pre-built foundation for developing websites and managing content. CMSs enable PHP programmers to produce and maintain content using a user-friendly interface rather than writing bespoke PHP code. They also provide a variety of additional features, including themes, plugins, and user management.

Libraries PHP has a large library and package collection that may be used to enhance its capabilities and add features to web applications. These libraries provide a wide range of functions, such as user authentication, picture processing, email handling, etc. They are often deployed with the help of package managers such as Composer.

Debugging and Testing

The PHP language includes several debugging and testing tools, such as Xdebug and PHPUnit, to assist developers in identifying and fixing bugs in their PHP script and ensuring that their script runs properly. These technologies include code coverage analysis, error reporting, and automated testing. They can assist developers in creating more robust and maintainable PHP code.

Development Best Practices

Here are some PHP programming best practices:

Use a Coding Standard

Code formatted consistently and easier to read and understand. PHP features various coding standards, including PSR-1 and PSR-2, which govern file name, indenting, and spacing restrictions. Following a coding standard can also assist in making code more manageable and less prone to problems.

Make Use of Version Control

Version control systems, such as Git, are critical for monitoring PHP code changes and interacting with other engineers. They let developers log changes, return to prior versions, and work on many features at the same time. Using version control can also assist in improving the robustness and maintainability of programming.

Clean up the Supplied Data

To avoid security risks like SQL injection and cross-site scripting (XSS), input data from users or other systems should always be sanitized. PHP has methods to assist in sanitizing input data, such as htmlspecialchars and mysqli real escape string.

Make Use of Prepared Statements

Prepared statements provide a safe way to interface with databases and protect against SQL injection threats. They enable developers to create a SQL query with placeholders for input data and then link the data to the placeholders during runtime. This makes inserting malicious code into searches considerably more difficult for attackers.

Avoid Using Global PHP Variables

Global variables may make PHP code harder to reason about and result in unexpected behavior. To handle state, employ object-oriented programming (OOP) techniques such as encapsulation and dependency injection.

PHP is a high-performance language, but improperly optimized code can result in sluggish page loads and a bad user experience. Minimizing database queries, leveraging caching, and optimizing pictures and other media are recommended practices for optimizing PHP code.

Document Your Code

Code with clear and succinct comments might be easier to comprehend and maintain. PHPDoc is a PHP code documentation standard, and tools such as phpDocumentor may produce documentation from PHPDoc comments.

Following these best practices can improve the security, maintainability, and performance of PHP code.