Darkvision

Infravision was a type of vision that many non-human species had, in addition to "normal sight", in Dungeons & Dragons and Advanced Dungeons & Dragons prior to version 3.0 of the game. In 3.0 and later, the ability was removed from the game and replaced with darkvision. The primary reason for the change was that, given it's name, infravision implied that the creature detected the infrared spectrum of light. However, creatures were described with having infravision out to some specified distance, such as 60 feet (18 m), or 120 feet (36 m), which is not how detecting infrared radiation (or visible spectrum radiation) works.

Like darkvision, infravision allows a creature to see in complete darkness, though not in or through darkness that is magical in origin. Seeing in darkness also caused problems in the logic of using the infrared spectrum to see, as most cave dwelling creatures had infravision but the majority of natural caves remain at a temperature equal to the surface's annual average temperature. Which means the rock of the cave would be the same temperature and a creature would not be able to discern the difference between a stalagmite in the center of a room from the floor underneath from the wall behind it.

Creatures able to use infravision are often able to shift between the normal spectrum of light and that of infravision at will. While making use of the infrared spectrum, their eyes glow red.

Creatures known to have infravision include:
 * Halflings
 * Dwarves
 * Drow
 * Duergar
 * Svirfneblin

Other reading

 * Rant: Infravision and Why It Should Be Destroyed