Dark nebulae are enormous interstellar clouds composed primarily of dense molecular gas and interstellar dust. These structures are characterized by their ability to absorb visible light, making them appear opaque or dark against the brighter backdrop of emission nebulae or stellar populations. They represent major reservoirs of material within galaxies, and their cold, dense cores are critical sites for star formation. Gravitational instabilities within the molecular cloud allow localized regions to collapse, accumulating enough mass and density to eventually initiate the stellar lifecycle.