fix(guide): simplify directory structure

guide/english/php/variables/data-types/index.md

@@ -0,0 +1,111 @@
+---
+title: PHP Data Types
+---
+
+# Data Types
+
+Variables can store data of different types such as:
+* String ("Hello")
+* Integer (5)
+* Float (also called double) (1.0)
+* Boolean ( 1 or 0 )
+* Array ( array("I", "am", "an", "array") )
+* Object
+* NULL
+* Resource
+
+## String
+
+A string is a sequence of characters. It can be any text inside quotes (single or double):
+
+#### Example
+```php
+$x = "Hello!";
+$y = 'Hello!';
+```
+
+## Integer
+
+An integer data type is a non-decimal number between -2,147,483,648 and 2,147,483,647.
+
+Rules for integers:
+
+* An integer must have at least one digit
+* An integer must not have a decimal point
+* An integer can be either positive or negative
+* Integers can be specified in three formats: decimal (10-based), hexadecimal (16-based - prefixed with 0x) or octal (8-based - prefixed with 0)
+
+#### Example
+```php
+$x = 5;
+```
+
+
+## Float
+
+A float (floating point number) is a number with a decimal point or a number in exponential form.
+
+#### Example
+```php
+$x = 5.01;
+```
+
+## Boolean
+
+A Boolean represents two possible states: TRUE or FALSE. Booleans are often used in conditional testing.
+
+```php
+$x = true;
+$y = false;
+```
+
+## Array
+
+An array stores multiple values in one single variable.  
+
+```php
+$colours = array("Blue","Purple","Pink");
+```
+
+
+## NULL Value
+
+Null is a special data type which can have only one value: NULL.  
+A variable of data type NULL is a variable that has no value assigned to it.  
+Variables can also be emptied by setting the value to NULL.  
+
+**Note:** If a variable is created without a value, it is automatically assigned a value of NULL.  
+
+```php
+<?php
+$x = "Hello world!";
+$x = null;
+?>
+```
+
+Output:  
+NULL
+
+
+## Object
+
+An object is a data type which stores data and information on how to process that data.  
+In PHP, an object must be explicitly declared.  
+First we must declare a class of object. A class is a structure that can contain properties and methods.
+
+**Example:**
+```php
+<?php
+class Car {
+    function Car() {
+        $this->model = "VW";
+    }
+}
+
+// create an object
+$herbie = new Car();
+
+// show object properties
+echo $herbie->model;
+?>
+```

guide/english/php/variables/index.md

@@ -0,0 +1,71 @@
+---
+title: Variables
+---
+
+## Variables
+# Creating (Declaring) PHP Variables
+
+Variables are "containers" for storing information.
+
+**Syntax:**
+
+```php
+<?php
+$txt = "Hello world!";
+$x = 5;
+$y = 10.5;
+?>
+```
+
+After the execution of the statements above, the variable $txt will hold the value Hello world!, the variable $x will hold the value 5, and the variable $y will hold the value 10.5.
+
+##### Note: When you assign a text value to a variable, put quotes around the value.
+
+##### Note: Unlike other programming languages, PHP has no command for declaring a variable. It is created the moment you first assign a value to it.
+
+# Rules for PHP variables:
+
+* A variable starts with the $ sign, followed by the name of the variable
+* A variable name must start with a letter or the underscore character
+* A variable name cannot start with a number
+* A variable name can only contain alpha-numeric characters and underscores (A-z, 0-9, and _ )
+* Variable names are case-sensitive ($age and $AGE are two different variables)
+
+# Output Variables
+
+The PHP echo statement is often used to output data to the screen.
+
+The following example will show how to output text and a variable:
+````php
+<?php
+$txt = "github.com";
+echo "I love $txt!";
+?>
+````
+
+The following example will produce the same output as the example above:
+````php
+<?php
+$txt = "github.com";
+echo "I love " . $txt . "!";
+?>
+````
+
+The following example will output the sum of two variables:
+````php
+<?php
+$x = 5;
+$y = 4;
+echo $x + $y;
+?>
+````
+
+# PHP is a Loosely Typed Language
+
+In the example above, notice that we did not have to tell PHP which data type the variable is.
+PHP automatically converts the variable to the correct data type, depending on its value.
+In other languages such as C, C++, and Java, the programmer must declare the name and type of the variable before using it.
+
+#### More Information:
+<!-- Please add any articles you think might be helpful to read before writing the article -->
+