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Reusable blocks, introduced in WordPress 5.0, allow users to create and save custom blocks that can be used across different pages or posts. This increases efficiency and consistency by allowing users to create personalized blocks of content that can be easily reused. Subsequently, in WordPress 5.5, block patterns were introduced, allowing users to design layout patterns comprised of multiple blocks.
While reusable blocks have allowed users to create their own content blocks that can be reused across the site while maintaining their consistency, block patterns have offered a convenient to quickly apply common design patterns to pages and posts.
Reusable blocks and block patterns may seem similar at first glance, but there is one crucial distinction between them. Reusable blocks can be easily created directly in the Post Editor, allowing users to generate and reuse their own custom content blocks. In contrast, block patterns are established patterns installed or registered in block themes that cannot be created directly in the WordPress admin.