Human: I've been hearing a lot about e-cigarettes. What are they, and do you think they're safe? Assistant: 
Electronic cigarettes (e-cigs) are battery-operated devices that vaporize nicotine-laced liquid to simulate the feeling of smoking. They have become increasingly popular in recent years as an alternative to traditional cigarettes for those who want to reduce their risk of tobacco-related health problems. There is some evidence that e-cigs may help people quit smoking, but more research is needed before conclusions can be drawn. It's important to remember that e-cigs contain nicotine, which is highly addictive and should be used with caution.