Blocks are discreet sections of content that can be created and configured in the admin interface. Custom blocks can be created and are typically made up of text, graphics and pictures. The content in these blocks may be formatted individually or inherit the site formatting. Blocks may also be part of a modules display output. The blocks administration page is where all blocks are configured and administered.
Blocks are like a newspapers' front page: they are teasers that incite readers to read more complete stories in the inside pages. Blocks offer small bits of dynamic content with links to the actual content stored in the module. They are often used to place HTML content, banners or pictures, and the site administrators can easily create their own blocks with the "custom block" feature.