Phototaxis is a biological phenomenon in which organisms exhibit a directional movement in response to light. This behavior is commonly observed in a wide range of organisms, from bacteria and algae to insects and animals. Phototaxis can be either positive or negative, depending on the organism's response to light. In positive phototaxis, organisms move towards a light source, while in negative phototaxis, they move away from it. This behavior is often crucial for the survival and navigation of organisms, helping them to find sources of food, avoid predators, and regulate their circadian rhythms. In research, phototaxis is studied to better understand the mechanisms and evolutionary advantages of light-responsive behavior in various organisms.