Octopuses squirt ink to create a dark, distracting cloud, allowing them to escape predators. The ink also contains compounds that irritate the predator's eyes and disrupt its sense of smell, further aiding the octopus's getaway. It is a defensive mechanism not for attack.
This fact belongs to the general category and contributes to expanding general knowledge. Understanding such facts not only makes you smarter but also helps connect ideas across different fields.