Even this may not be the correct terms, I'll use them anyway .
There are two display mode in qE's modules. Windowed aka inline mode, and full screen aka full page mode.
As the name implied, in windowed mode, the module displayed within another content. Example modules:
→ Above image show the Portal Module in Inline Mode. The module is displayed inside other content.
Also as the name implied, in full screen mode, you don't see any other contents, except the module itself (and may be other windowed modules). Example modules:
→ Above image show the Portal Module in Full Page Mode. The module is displayed exclusively without other content than itself.
Some modules may have both mode, either at the same time, or at different time. Example modules:
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