Php script programming language

What is PHP? Learn All About the Scripting Language

What is PHP, and what is PHP used for exactly? PHP is a server-side scripting programming language that’s used to develop static or dynamic websites, or even web applications.

What does PHP stand for? PHP stands for Hypertext Preprocessor, but you may recognize it as the old acronym for “Personal Home Pages.”

A script is a set of programming instructions interpreted at runtime. A scripting language is responsible for interpreting scripts at runtime. The primary objective of a script is to escalate the performance of various tasks in an application.

But what is PHP programming, and how can you use it? We’ll cover all that today — read on to gather an introduction to PHP and learn all about its uses in the computer world.

What is PHP Programming?

PHP stands for hypertext preprocessor. The PHP programming language is a scripting language used widely across the globe, primarily for web development. You can embed PHP into HTML and work after that too.

Moreover, PHP is server-side, whereas other programming languages like JavaScript are client-side. The major difference between the two is that PHP code is executed on the server that generates HTML, and is sent directly to the client. While the client can see the results by running the script, they cannot access the underlying code.

If you are a beginner, PHP is an extremely simple language for you to learn. It also comprises advanced features for professional programmers. You can start by writing simple scripts and master the PHP programming language gradually.

Now, let’s dive into the syntax of PHP.

Syntax of PHP

PHP syntax is pretty simple. A PHP file can also include HTML or client-side script as JavaScript.

Here is the basic syntax of PHP:

The display screen shows, “I love programming.”

When using PHP, keep the following in mind:

• While not essential, some prior understanding of HTML is ideal before learning the PHP programming language.
• To handle database-powered applications with PHP, use database management systems or DBMS .
• You will need XML or JavaScript to build advanced interactive applications with PHP.

How to Write a Program in PHP

Writing a program in PHP is extremely easy. See the below example:

Let’s move ahead and know why to use PHP.

Why PHP?

As you know, there are a plethora of programming languages available for you to work with as a web developer. So, what makes PHP stand out from the others? Here are a few benefits of using PHP:

• PHP is a free and open-source scripting language.
• PHP is a server-side scripting language . You can install it on the server; however, the clients who request the resources from the server don’t have to install PHP.
• It is cross-platform , allowing you to use it on various operating systems like Windows, macOS, Linux, etc.
• PHP comes with a built-in support system , which means that you can use PHP with various database management systems such as Oracle, Postgres, ODBC, MS, and SQL Server.
• Most web hosting servers support PHP.
• PHP provides you with a huge online community with all kinds of support, including documentation guides and problem-solving posts.
• PHP is easy to learn , especially if you have a basic knowledge of other programming languages.
• Vast text-processing features like PCRE and Perl

In addition, PHP offers a remarkable feature by supporting a wide range of databases. For example, you can use database-specific extensions like MySQL to write a database-enabled web page, use an abstraction layer such as PDO, or even build a connection to a database with the ODBC extension.

Furthermore, while using PHP, you can use both object-oriented programming and procedural programming. You are not just bound to output HTML; rather, you can output any text like XML or XHTML. PHP can auto-generate search files and save them, helping to protect the server-side from forming a cache for the dynamic content.

Now that we know some of PHP’s benefits, let’s get into the PHP extensions.

PHP Extensions

PHP files are saved with the “.php” extension. Some of the earlier PHP file extensions include:

Where is PHP Used?

There are various fields where you can use PHP, and but these are the three most vital areas to use it:

Command-Line Scripting

Several tasks run in the background of a web server besides web applications for the databases. Each task concludes after a designated amount of time. Therefore, every task has its timeline.

Here’s an example of command-line scripting in PHP:

Suppose you have to send an invitation email to your subscribers on a mailing list. You can carry out this task via web scripting. However, the process gets trickier when you reach a few hundred subscribers. And, if there are thousands of subscribers, a web script will only have a couple of minutes for execution, a period known as maximum execution time. At the end of this period, the web server terminates the web script and fails to send the email to a portion of the subscribers.

PHP command-line scripting can resolve this issue:

With command-line scripts, there is no maximum execution time. The scripts can run as long as the server is active.

Hence, with the help of command-line scripting, any kind of time-consuming tasks such as transferring files to another server via FTP or backing up a complete website or database can be done seamlessly.

Server-Side Scripting

Server-side scripting is the most common and frequently used field for PHP. It requires three vital components: a webserver, a web browser, and a PHP parser.

With server-side scripting, you must run the web server with installed PHP. Moreover, you can easily access and run any PHP program output through a web browser.

Writing Desktop Applications

If you want to develop a desktop application and a GUI, PHP may not be the perfect solution for you. However, to access some advanced PHP features, you can use PHP-GTK in your client-side applications to write programs.

PHP-GTK is an extension of PHP. However, you may not find it in the main distribution. To access PHP-GTK, visit the official website .

PHP Data Types and Operators

PHP supports a wide set of data types, such as:

PHP Integer

A non-decimal number within the range of -2,147,483,648 and 2,147,483,647 is an integer data type. A number is an integer only when at least one digit is either positive or negative. Take a look at the below command that takes $z as an integer, with the function var_dump returning the value:

PHP String

A PHP string is any sequence of characters. Here’s the syntax to use a string in PHP:

PHP Float

A floating-point number is any number with a decimal point or a number that’s present in an exponential form.

PHP Array

An array holds multiple values in one variable:

PHP Boolean

A Boolean is used for conditional testing, and it tells you two states:

Now, let’s move on to the PHP operators.

PHP Operators

Operators are primarily used to perform various operations on variables. Different operators in PHP include:

• Logical operators
• Arithmetic operators
• Array operators
• Assignment operators
• Comparison operators

Logical Operators

Logical operators help to combine conditional statements:

Name of the operator

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PHP Introduction

Before you continue you should have a basic understanding of the following:

If you want to study these subjects first, find the tutorials on our Home page.

What is PHP?

• PHP is an acronym for «PHP: Hypertext Preprocessor»
• PHP is a widely-used, open source scripting language
• PHP scripts are executed on the server
• PHP is free to download and use

PHP is an amazing and popular language!

It is powerful enough to be at the core of the biggest blogging system on the web (WordPress)!
It is deep enough to run large social networks!
It is also easy enough to be a beginner’s first server side language!

What is a PHP File?

• PHP files can contain text, HTML, CSS, JavaScript, and PHP code
• PHP code is executed on the server, and the result is returned to the browser as plain HTML
• PHP files have extension » .php «

What Can PHP Do?

• PHP can generate dynamic page content
• PHP can create, open, read, write, delete, and close files on the server
• PHP can collect form data
• PHP can send and receive cookies
• PHP can add, delete, modify data in your database
• PHP can be used to control user-access
• PHP can encrypt data

With PHP you are not limited to output HTML. You can output images or PDF files. You can also output any text, such as XHTML and XML.

Why PHP?

• PHP runs on various platforms (Windows, Linux, Unix, Mac OS X, etc.)
• PHP is compatible with almost all servers used today (Apache, IIS, etc.)
• PHP supports a wide range of databases
• PHP is free. Download it from the official PHP resource: www.php.net
• PHP is easy to learn and runs efficiently on the server side

What’s new in PHP 7

• PHP 7 is much faster than the previous popular stable release (PHP 5.6)
• PHP 7 has improved Error Handling
• PHP 7 supports stricter Type Declarations for function arguments
• PHP 7 supports new operators (like the spaceship operator: )

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What is PHP?

PHP (recursive acronym for PHP: Hypertext Preprocessor ) is a widely-used open source general-purpose scripting language that is especially suited for web development and can be embedded into HTML.

Nice, but what does that mean? An example:

Example #1 An introductory example

Instead of lots of commands to output HTML (as seen in C or Perl), PHP pages contain HTML with embedded code that does «something» (in this case, output «Hi, I’m a PHP script!»). The PHP code is enclosed in special start and end processing instructions that allow you to jump into and out of «PHP mode.»

What distinguishes PHP from something like client-side JavaScript is that the code is executed on the server, generating HTML which is then sent to the client. The client would receive the results of running that script, but would not know what the underlying code was. You can even configure your web server to process all your HTML files with PHP, and then there’s really no way that users can tell what you have up your sleeve.

The best part about using PHP is that it is extremely simple for a newcomer, but offers many advanced features for a professional programmer. Don’t be afraid to read the long list of PHP’s features. You can jump in, in a short time, and start writing simple scripts in a few hours.

Although PHP’s development is focused on server-side scripting, you can do much more with it. Read on, and see more in the What can PHP do? section, or go right to the introductory tutorial if you are only interested in web programming.

User Contributed Notes

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