Update Student-Facing Documentation

docs/ABOUT.md

@@ -1,15 +1,15 @@
-PHP is a server-side language suited towards web development. The acronym is recursive, standing for *PHP: Hypertext Preprocessor*. 
+PHP is a server-side language suited towards web development. The acronym is recursive, standing for _PHP: Hypertext Preprocessor_.
 
 Considerably more versatile than CGI scripting, PHP is often used to add interactivity to plain HTML and bolster web frameworks.
 
-The language can be employed on any operating system. PHP is supported by most common web servers and is often handled through an interpreter module. This combines static web code with dynamic inclusions. 
+The language can be employed on any operating system. PHP is supported by most common web servers and is often handled through an interpreter module. This combines static web code with dynamic inclusions.
 
-PHP isn't just a web server framework. It's also useful for command-line scripting (headless parsing) and developing GUIs. 
+PHP isn't just a web server framework. It's also useful for command-line scripting (headless parsing) and developing GUIs.
 
 You should learn PHP because:
 
-* it's an Open Source language
-* it's well-documented and supported
-* it's compatible with most common web servers
-* it's easy to pick up and start learning
-* it's highly scalable and extensible
+- it's an Open Source language
+- it's well-documented and supported
+- it's compatible with most common web servers
+- it's easy to pick up and start learning
+- it's highly scalable and extensible

docs/INSTALLATION.md

@@ -1,6 +1,6 @@
 ### Which version to chose?
 
-We encourage to use a stable PHP release with active support. Currently this is **PHP 7.2 and 7.3**. Details on current releases and their timelines can be found at [php.net/supported-versions](https://www.php.net/supported-versions.php).
+We encourage to use a stable PHP release with active support. Currently this is **PHP 7.3 and 7.4**. Details on current releases and their timelines can be found at [php.net/supported-versions](https://www.php.net/supported-versions.php).
 
 ### Install PHP
 
@@ -28,7 +28,7 @@ For further instructions, read the manual on [Installation on Unix systems](http
 
 #### macOS
 
-Normally macOS comes with PHP installed. There are other pre-built options available, including [MAMP](http://www.mamp.info/en/) an [php-osx.liip.ch](https://php-osx.liip.ch/).
+Normally macOS comes with PHP installed, but it is often an outdated version. There are other pre-built options available, including [MAMP](http://www.mamp.info/en/) and [php-osx.liip.ch](https://php-osx.liip.ch/).
 
 For further instructions, read the manual on [Installation on macOS](https://www.php.net/manual/en/install.macosx.php).
 
@@ -44,17 +44,16 @@ For further instructions, read the manual on [Installation on Windows systems](h
 
 If you want to use a different OS, see instruction on [php.net/manual/en/install](https://www.php.net/manual/en/install.php).
 
-
 ### Install PHPUnit
 
 #### Via Composer
 
-PHPUnit can be installed globally via [Composer](https://getcomposer.org), using the following command.
+PHPUnit version 8 can be installed globally via [Composer](https://getcomposer.org), using the following command.
 
 ```bash
-$ composer global require phpunit/phpunit
+> composer global require phpunit/phpunit ^8
 ```
 
 #### Manual installation
 
-If you are not using Composer package manager, follow the official [Installing PHPUnit instructions](https://phpunit.de/manual/6.5/en/installation.html).
+If you are not using Composer package manager, follow the official [Installing PHPUnit instructions](https://phpunit.readthedocs.io/en/8.5/installation.html).

docs/LEARNING.md

@@ -2,9 +2,9 @@
 
 Exercism provides exercises and feedback but can be difficult to jump into for those learning PHP for the first time. These free resources can help you get started:
 
-[Laracasts - The PHP Practitioner Video Tutorials](https://laracasts.com/series/php-for-beginners)  
-[PHP Documentation](http://php.net/docs.php)  
-[PHP The Right Way](http://www.phptherightway.com/)  
-[Codecademy's PHP Course](https://www.codecademy.com/learn/php)  
-[StackOverflow](http://stackoverflow.com/questions/tagged/php)  
+[Laracasts - The PHP Practitioner Video Tutorials](https://laracasts.com/series/php-for-beginners)
+[PHP Documentation](http://php.net/docs.php)
+[PHP The Right Way](http://www.phptherightway.com/)
+[Codecademy's PHP Course](https://www.codecademy.com/learn/php)
+[StackOverflow](http://stackoverflow.com/questions/tagged/php)
 [PHP Pandas (Online Book)](https://daylerees.com/php-pandas/)

docs/RESOURCES.md

@@ -1,12 +1,12 @@
 ## Recommended Learning Resources
 
-* [PHP The Right Way](http://www.phptherightway.com/)
-* [PHP Best Practices](https://phpbestpractices.org/)
-* [Best practices for Modern PHP Development](https://www.airpair.com/php/posts/best-practices-for-modern-php-development)
-* [PHP Cheatsheets](http://phpcheatsheets.com/)
+- [PHP The Right Way](http://www.phptherightway.com/)
+- [PHP Best Practices](https://phpbestpractices.org/)
+- [Best practices for Modern PHP Development](https://www.airpair.com/php/posts/best-practices-for-modern-php-development)
+- [PHP Cheatsheets](http://phpcheatsheets.com/)
 
 ## Recommended References
 
-* [PHP.net](http://php.net/)
-* [Composer dependency manager](https://getcomposer.org/)
-* [PHPUnit testing framework](https://phpunit.de/)
+- [PHP.net](http://php.net/)
+- [Composer dependency manager](https://getcomposer.org/)
+- [PHPUnit testing framework](https://phpunit.de/)

docs/TESTS.md

@@ -1,5 +1,5 @@
 Execute the tests with:
 
-```
-$ phpunit filename.php
+```shell
+> phpunit file_to_test.php
 ```