Smoking cigarettes may be passé, but nicotine is still addictive, hence the popularity of electronic cigarettes. E-cigarettes contain a liquid solution of nicotine that’s vaporized and then inhaled — a process referred to as “vaping.” They’re powered by a small rechargable battery and emit a puff of smoke that has no scent. Proponents claim users avoid inhaling tar and other harmful chemicals found in cigarettes, but health benefits of e-cigs have not been proven. Still, they’re fast becoming a smoking-cessation tool. When Vapor Den opened its Berkeley store in 2011, it was among the first brick-and-mortar stores in the country to sell e-cigarettes and accessories, according to owner Jacque Lacey. It has since expanded, opening stores in San Francisco and online. Similar to a cannabis dispensary, Vapor Den offers a large menu of e-cigs with flavors such as mint, cherry, and tobacco, as well as differing levels of nicotine strength. The store also offers guidance on how e-cigs work, how to charge them, and other tips for first-timers.