Tooltips in Inline Manual refer to both a type of Topic and a style of Launcher.
When creating a new Topic with the Authoring Tool, one of the choices is Tooltips:
You can create the same variety of content with Tooltips that you can create with Walkthroughs, but there's one key difference: user engagement with Tooltip Topics is not recorded by Inline Manual Analytics. This makes them ideal for hints on form fields, for example, or any content where you don't want or need performance statistics available in Analytics.
Tooltips are also a style of a Launcher in Inline Manual and are small, static icons with a question mark inside. You can launch popover messages or even whole guides with them, so they're a great way to shed light on known trouble spots in your application.
To learn how to create engaging and supportive user experiences with Tooltip Launchers, check out our article Launchers in Inline Manual.