What is a stream?
Streams are a network object or file that can be read or written to.
Wrappers provide a way to route to these streams.
What is a Scheme?
scheme://target
More info: https://www.php.net/manual/en/intro.stream.php
PHP Stream Wrapper: https://www.php.net/manual/en/class.streamwrapper.php
What's the use case for Stream Wrappers?
This module provides wrappers to fetch system files: https://www.drupal.org/project/system_stream_wrapper
PHP has built in wrappers for things like file:// and http://.
Drupal adds ones like public:// and private://
https://api.drupal.org/api/drupal/core%21lib%21Drupal%21Core%21StreamWr…