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Instructions
Blocks are individual pieces of your site’s web page layout. They are placed inside the regions (see Section 2.1, “Concept: Regions in a Theme”) of your theme, and can be created, removed, and rearranged in the Block layout (admin/structure/block) administration page. Examples of blocks include the Who’s online listing, the main navigation menu, and the breadcrumb trail. The main page content is also a block.
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