PHP stands for Hypertext Processor and is a very powerful, open-source and popular server-side scripting language that is used by developers to create dynamic and interactive web pages. The programming language allows developers to form content that can interact with different databases and is used to develop web-based software applications. The popular programming language is used by the tech giants like Google, Facebook and Yahoo and can be embedded into other front-end technologies like HTML.
There is no rule of thumb as to what one should already know before learning PHP. It is advisable to have a basic understanding of the front-end technologies like HTML and CSS in order in order to offer a seamless user experience on a responsive platform. Since PHP serves to establish a connection between content and database, an understanding of the database management system and software like MySQL will also useful.
Even though it is totally optional, a proper understanding of the programming languages like Java, C and C++ can accelerate the process of learning PHP. PHP has the functional units like loops and arrays and thus having even a basic knowledge of the programming languages will obviously help.
PHP is a very powerful and a very versatile programming language that can serve a lot of different purposes.
Server-side Scripting: This is the main function of PHP and a developer needs three things to perform it. The developer needs a one PHP parser to convert a human-readable language to a computer-readable form, a web server to execute the files forming the web pages and a web browser to exhibit content or access the program output.
Command-line Scripting: You can execute or run a PHP script without a web browser or a web server and using just a PHP parser. This function of PHP is normally used for simpler text processing tasks.
Desktop Application Development: Another function of PHP is to create client-side applications. Such applications typically have graphical user interfaces. Advanced PHP features can be used to develop such applications.
Graphic Design and Image Processing: PHP scripts are also used for manipulating image content along with text content. Different image processing libraries like ImageMagick, GD Library and Imagine can be integrated into PHP applications that can then manipulate the images.
PHP is one of the most widely used server-side scripting languages because of the efficient, quick and practical nature of its services.
PHP Shell is a script or program written in PHP (Php Hypertext Preprocessor) which provides us with Linux Terminal (Shell is a vast concept) in Browser. PHP Shell allows user to execute most of the shell commands in browser, some cannot be executed due to PHP limitations.
We can insert PHP script or code anywhere in the document. A PHP script or code starts with <?php and ends with ?>:
PHP code goes here
For Example (PHP Hello World):
echo "Hello World!";