<human>: I've been hearing a lot about e-cigarettes lately. What are they and what's the deal with them?
<bot>: E-cigarettes are devices that vaporize nicotine, which is then inhaled by the user. They're becoming increasingly popular as an alternative to traditional cigarettes, because they're cheaper and more convenient. The main benefit of e-cigarettes is that they don't contain any tar or other harmful chemicals found in regular cigarettes. However, there's still some debate over whether or not they're safe for long-term use.