It is often used in the context of:
* Camera obscura: A device that uses a lens or pinhole to project an image onto a surface, traditionally a darkened room. The name highlights the fact that the interior of the device is dark, creating a space for the image to be projected.
* Figuratively: Obscura can also be used to suggest something obscure, hidden, or secret. For example, "the truth of the matter remained obscura to most."
The word "obscura" is not often used on its own, but rather appears in compound words like "camera obscura" or "obscurantism" (which refers to the practice of opposing enlightenment or progress).