PHP Tutorial

PHP is a powerful scripting language designed for web development but also used as a general-purpose programming language.

Setting Up a PHP File

All PHP files should have a .php file extension. A PHP file normally contains HTML tags, and some PHP scripting code. Below is a simple PHP file:

<!DOCTYPE html>
<html>
<body>

<h1>My first PHP page</h1>

<?php
echo "Hello World!";
?>

</body>
</html>

Comments in PHP

Comments in PHP are used to leave notes or to prevent the execution of code without deleting it. PHP supports several ways of commenting:

// This is a single-line comment

# This is also a single-line comment

/*
This is a multiple-lines comment block
that spans over multiple
lines
*/

Variables in PHP

Variables in PHP are represented by a dollar sign followed by the name of the variable. The variable name is case-sensitive. Here's an example:

<?php
$txt = "Hello world!";
$x = 5;
$y = 10.5;
?>

PHP Echo and Print Statements

Echo and print are more or less the same. They are both used to output data to the screen. The differences are small: echo has no return value while print has a return value of 1 so it can be used in expressions. Echo can take multiple parameters (although such usage is rare) while print can take one argument. Echo is marginally faster than print. Here's an example:

<?php
echo "<h2>PHP is Fun!</h2>";
echo "Hello world!<br>";
echo "I'm about to learn PHP!<br>";
echo "This ", "string ", "was ", "made ", "with multiple parameters.";
?>

PHP Data Types

PHP supports the following data types: String, Integer, Float (floating point numbers - also called double), Boolean, Array, Object, NULL, and Resource.

Here's an example of PHP string:

<?php
$x = "Hello world!";
$y = 'Hello world!';

echo $x;
echo "<br>"; 
echo $y;
?>

This is a basic introduction to PHP. PHP is a vast language with many features like conditional statements, loops, functions, error handling, form handling, file handling, and more. I recommend checking out some comprehensive PHP tutorials or documentation for more advanced topics.

PHP Tutorial

PHP Flow Control

PHP Functions

PHP String

PHP Array

PHP Date Time

PHP Object Oriented

Regular Expression

PHP Cookie & Session

PHP Error & Exception handling

MySQL in PHP

PHP File Directory

PHP Image Processing