Phototaxis

Phototaxis is an organismal response to light. When exposed to light, said organism either moves towards or away from the light, depending on the species. Movement towards a light source is positive phototaxis, and movement away from a light source is negative phototaxis. For example, cockroaches will move away from any light source, and thus exhibit negative phototaxis. Moths will move towards most sources of light, and thus exhibit positive phototaxis.

Synonyms:
Phototropism