Install Composer

Composer is an extremely commonly used PHP package manager. You will need/want it if you're working with PHP.

Run the following to install composer and make it available to the entire system. This requires root access. You can run these commands from any folder as they will clean up after themselves:

sudo su
php -r "copy('https://getcomposer.org/installer', 'composer-setup.php');"
php composer-setup.php
mv composer.phar /usr/local/bin/composer
rm composer-setup.php

You can now access composer from anywhere!