Block Patterns have been available since the WordPress 5.5 release. Block patterns make it simple and fun to create complex, beautiful layouts, using combinations of text and media that you can mix and match.
Each Pattern is a collection of different blocks carefully put together to help you produce great looking blog posts and pages in the Editor.
Recently, We have been creating a Reusable Block. Adding it to a post or a page and then converting it to a regular block. Then making any changes that we want. Block patterns remove the need for this workaround.
We are also experimenting with putting the code in as a plugin so that we can create our own set of Block Patterns and be able to add them to our different WordPress websites.
Don Quixote
Above is an example of a Cover that is in the default Block Patterns added by WordPress.
Here are some helpful links about Block Patterns:
The WordPress Block Patterns Resource List