composer is PHP package manager, to install, run
curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer
Install Packages
Run this every time you change composer.json or pull newer copy from git.
composer install
Show Installed Packages
composer show -i
Update Software
Only run this if you need to update software versions. Don’t run it in production. Only run when you are project maintainer and need everyone else use latest version of packages.
composer update