Here's what each of the topic display category Layout Options does:
Default
This option displays the full body of all articles on the topic display category page. The topic display category title is a Heading 1; each article title is a Heading 2 and displays the full text of the article beneath it.
Accordions
This option places each article into an expandable block, with the article title (or short title) displayed as the block heading. The blocks are collapsed and include a + / - icon displayed before them
Tabs
This option creates a separate tab for each article, using the article's title (or short title) as the tab label.
See Topic display categories for more details and screenshot comparisons of these settings!
