Night vision was the ability to see in darkness.
Gallifreyans had the ability to see in the dark far better than humans could. (PROSE: Lucifer Rising) Some bloodlines, like the Corsair's, had particularly keen night vision even compared to others of their kind; (PROSE: The Bloodletters, The Book of the War) this was most prominent in members of House Arpexia. (PROSE: The Book of the War)
Leela, as a huntress of the Sevateem, could see very well in the dark. (AUDIO: The Darkness of Glass)
According to the First Doctor, it was a fallacy that cats could see in the dark. Their eyes did, however, allow for better night vision than humans had, as their irises dilated at night. As the Doctor noted, the Sensorites' eyes were the complete opposite, completely dilating in the light, and therefore contracting in darkness. As a result, the Sensorites had very poor night vision. (TV: The Sensorites)
UNIT used gas masks with night vision capabilities. They were, however, unable to see through the clone feed fog. (TV: The Poison Sky)
The paranormal TV show Scared Stiff was partially recorded with night vision cameras. (PROSE: Scared Stiff)