Computer-induced health problems can be an umbrella term for the various problems a computer user can develop from extended and incorrect computer use. A computer user may experience many physical health problems from using computers extensively over a prolonged period in an inefficient manner. The computer user may have poor etiquette when using peripherals, for example incorrect posture. Reportedly, excessive use of electronic screen media can have ill effects on mental health related to mood, cognition, and behavior, even to the point of hallucination. Prevention methods include physical activity breaks, hydration, ergonomic posture, and regular eye exercises such as the 20-20-20 rule (every 20 minutes, look at something 20 feet or 6 meters away for 20 seconds).[better source needed]