1.3.3: Composer JSON Directives
require: specifies which modules should be included. This is a great overview of versions and their constraints.
require-dev: this is used when
composer install --dev is specified. This is often used in your development environment to also include tooling like PHPUnit.
files: These are loaded on every request. Magento uses this to initialize module loading in
psr-4: This is the most common autoload initialization clause. This associates a namespace with a path. For example, this file declares that
Bold\OrderCommentis associated with the base directory, found in
vendor/boldcommerce/magento2-ordercomments. All classes inside this directory are located as they started