Content gathered from different sources web, w3schools.com, derek banas youtube channels among others.
PHP code is executed on the server. 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 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"
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, PDF files, and even Flash movies. You can also output any text, such as XHTML and XML.
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
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: <=> )
php can be embbeded into HTML file, just place any php code between tags <?php ?>
like so:
<?php
your php code goes here
?>
variable declaration starts with a $ followed with the variable name starting with a letter followed by any letter, number or underscore.
$f_name="Ai"; //variable with string datatype in double quotes (single quotes can be used too).
$l_name='Dj';
$age=44; //integer
$height=1.91; //float
$can_vote=true; //boolean
$address=array('street => '1 Hacker Way', 'city'=> 'Palo Alto');
$state = NULL; //variable has no value;
define('PI',3.14159265);