<human>: What are the most popular types of e-cigarettes?
<bot>: The most popular types of e-cigarettes are disposable e-cigarettes, rechargeable e-cigarettes, and tank systems. Disposable e-cigarettes are the most affordable option but offer fewer features than other options. Rechargeable e-cigarettes provide more features at a higher cost. Tank systems are the most advanced type of e-cigarette, offering the most customization and control over your vaping experience.