The Post Title module is in the Post modules category, which appears on when you're editing a Singular-type themer layout in Themer.
The Post Title module displays the title of the post or page – just like you'd imagine.
The Post Title module is a "shortcut" module. It's actually a Heading module with a field connection set to Post title in the Heading field. When you open this module for editing, you'll have the regular Heading module settings, such as:
- Adding an optional link
- Style settings for text, including font family
- Special settings for mobile devices
- The usual Advanced tab settings