Add PHP

php/README.md

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+name: PHP
+
+description: A powerful language for web development
+
+color: A6D8FF
+
+icon: https://img.enkipro.com/3b93389af57a5f6359e50d207274df29.png
+availableAspects:
+  - introduction

php/php-core/README.md

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+name: PHP Core
+
+description: Basic Syntax and Functionality
+
+core: true
+
+sections:
+  '0':
+    - intro-to-php
+    - variables-php
+    - data-types-php
+    - control-flow-i-php
+    - logical-operators-php
+    - looping-php
+    - more-data-types-php

php/php-core/control-flow-i-php/README.md

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+name: Control Flow I
+
+description: Explore PHP's fundamental control flow.
+
+insights:
+  - if-statements-php
+  - comparison-operators-php
+  - if-else-statements-php
+  - nested-if-else-statements-php
+
+aspects:
+  - introduction

php/php-core/control-flow-i-php/comparison-operators-php.md

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+---
+author: Stefan-Stojanovic
+tags:
+  - introduction
+type: normal
+category: must-know
+practiceQuestion:
+  formats:
+    - fill-in-the-gap
+  context: standalone
+revisionQuestion:
+  formats:
+    - fill-in-the-gap
+  context: standalone
+---
+
+# Comparison Operators
+
+---
+
+## Content
+
+Comparison operators can be used to compare various types of data, including numbers, strings, and booleans:
+
+
+| Operator |             Name            |
+|:--------:|:---------------------------:|
+| ==       | is equal to                 |
+| !=       | is not equal to             |
+| <        | is less than                |
+| <=       | is less than or equal to    |
+| >        | is greater than             |
+| >=       | is greater than or equal to |
+
+```php
+if ($num < 5) { // true
+  echo "$num is less than 5";
+}
+// 1 is less than 5
+
+if ($num != 2) { // true
+  echo "$num doesn't equal 2";
+}
+// 1 doesn't equal 2
+```
+
+
+---
+
+## Practice
+
+Finish the code to output "$num is greater than or equal to 3" if the condition evaluates to
+
+```php
+??? = 5;
+if ($num ??? 3) {
+  echo "$??? is greater than or equal to 3";
+}
+```
+
+- $num
+- `>=`
+- num
+- 5
+
+
+---
+
+## Revision
+
+Finish the code to output "$num is greater than or equal to 3" 
+
+```php
+??? = 5;
+if ($num ??? 3) {
+  echo "$??? is greater than or equal to 3";
+}
+```
+
+- $num
+- `>=`
+- num
+- 5

php/php-core/control-flow-i-php/if-else-statements-php.md

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+---
+author: Stefan-Stojanovic
+tags:
+  - introduction
+type: normal
+category: must-know
+practiceQuestion:
+  formats:
+    - fill-in-the-gap
+  context: standalone
+revisionQuestion:
+  formats:
+    - fill-in-the-gap
+  context: standalone
+---
+
+# If else Statements
+
+---
+
+## Content
+
+We can extend the `if` statement to include an `else` clause, which will be executed if the condition is not met.
+
+```php
+$num = 1;
+if ($num == 0) { // false
+  echo "num equals 0";
+} else { // will execute if condition is false
+  echo "num doesn't equal 0";
+}
+
+// num doesn't equal 0
+```
+
+---
+
+## Practice
+
+What does the following code snippet print?
+
+```php
+$x = 4;
+if ($x <= 3) {
+  echo 'x is smaller';
+} else {
+  echo 'x is larger';
+}
+```
+
+???
+
+- x is larger
+- x is smaller
+
+---
+
+## Revision
+
+What does the following code snippet print?
+
+```php
+$x = 13;
+if ($x == 13) {
+  echo 'true';
+} else {
+  echo 'false';
+}
+```
+
+- true
+- false

php/php-core/control-flow-i-php/if-statements-php.md

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+---
+author: Stefan-Stojanovic
+tags:
+  - introduction
+type: normal
+category: must-know
+practiceQuestion:
+  formats:
+    - fill-in-the-gap
+  context: standalone
+revisionQuestion:
+  formats:
+    - fill-in-the-gap
+  context: standalone
+---
+
+# If Statements
+
+---
+
+## Content
+
+The flow of a PHP program depends on the order in which individual commands are executed. Control flow statements like if...else allow us to manage the order using conditions.
+
+```php
+if (condition) {
+  // execute this code
+}
+```
+
+The script will only execute the code if the condition has been met.
+
+```php
+$num = 5;
+if ($num > 0) {
+  echo "$num is a positive number";
+}
+// Output: 5 is a positive number
+```
+
+If the condition `$num > 0` evaluates to `false`, this code would not output anything.
+
+---
+## Practice
+
+What does the following code snippet print?
+
+```php
+$num = 5;
+if ($num > 0) {
+  echo "$num is a positive number";
+}
+```
+
+???
+
+- 5 is a positive number
+- nothing
+
+---
+
+## Revision
+
+What does the following code snippet print?
+
+```php
+$num = 0;
+if ($num > 0) {
+  echo "num is 0";
+}
+```
+
+- nothing
+- num is 0

php/php-core/control-flow-i-php/nested-if-else-statements-php.md

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+---
+author: Stefan-Stojanovic
+tags:
+  - introduction
+type: normal
+category: must-know
+practiceQuestion:
+  formats:
+    - fill-in-the-gap
+  context: standalone
+revisionQuestion:
+  formats:
+    - fill-in-the-gap
+  context: standalone
+---
+
+# Nested if else Statements
+
+---
+
+## Content
+
+In PHP, we can have an `if-else` statement inside another `if-else` statement. This is called nesting.
+
+Nested `if-else` statements can be used to perform complex decision making.
+
+Here's a basic example:
+```php
+$age = 20;
+
+if($age >= 18){
+  if($age <= 60){
+    echo "You are an adult.";
+  }
+  else{
+    echo "You are a senior.";
+  }
+}
+else{
+  echo "You are not an adult.";
+}
+
+// Output: "You are an adult."
+```
+
+---
+
+## Practice
+
+What is the output of the following code?
+
+```php
+$age = 70;
+
+if($age >= 18){
+  if($age <= 60){
+    echo "You are an adult.";
+  }
+  else{
+    echo "You are a senior.";
+  }
+}
+else{
+  echo "You are not an adult.";
+}
+// Output: ???
+```
+
+- You are a senior.
+- You are not an adult.
+- You are an adult.
+
+---
+
+## Revision
+
+What is the output of the following code?
+
+```php
+$age = 15;
+
+if($age >= 18){
+  if($age <= 60){
+    echo "You are an adult.";
+  }
+  else{
+    echo "You are a senior.";
+  }
+}
+else{
+  echo "You are not an adult.";
+}
+// Output: ???
+```
+
+- You are not an adult.
+- You are a senior.
+- You are an adult.

php/php-core/data-types-php/README.md

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+name: Data Types
+
+description: Learn about basic data types in PHP.
+
+insights:
+  - basic-data-types-php
+  - basic-data-types-php-ii
+  - basic-data-types-php-iii
+  - basic-data-types-php-iv
+
+aspects:
+  - workout
+  - deep