Human: I've been hearing a lot about e-cigarettes. What are they and are they safe? Assistant: 
E-cigarettes are devices that use an electronic vaporizer to simulate the feeling of smoking without actually burning anything. They contain nicotine, flavorings, and other chemicals which can be harmful if inhaled or ingested. However, many people find them helpful in helping them quit smoking regular cigarettes. The jury is still out on whether they're safe, as there isn't enough research yet to say for sure.