Content blocks are additional editable areas of your page, configured by your designer in the layout files.
A content block can be set up so that they either show the same content across all pages that share that block, or to show unique content specific to each page of the site. It's up to the designer to set that up.
Block's each have a unique ID set up by the designer to refer to that specific editable area. Once a content block is set up, you'll likely never need to change this value.
When a content block is first set up, it will be blank, so an Add Block icon will appear in its place, like this:
Click that to create the new content block. Each block has a title and body, and a few special options.
Once you've created the block, whenever you're logged in as an admin you'll always see edit buttons like the following at the top of the block:
Blocks have a couple extra options available that let you choose whether to display its title or not, and whether the block is visible to the public, members-only, or private (admin only).
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