You're about to get a preview of a premium Guide. Guides are a feature of theSkimm App that make it easier to go down a rabbit hole on the biggest issues in your newsfeed. They go beyond what you see in the Daily Skimm to give you the history and context of everything from climate change to artificial intelligence to the rising cost of college. Plus, they include exclusive audio stories just for app subscribers. Editor's note: This article was updated on Dec. 19, 2019 to reflect the latest death toll from vaping-related lung illnesses. The Story Millions of people use e-cigarettes. And that has federal regulators very worried. How’d we get here? It’s an evolution that started with traditional cigarettes, which first became popular in the early 20th century, and were seen as a symbol of sophistication and glamour. That started to change in the mid-1900s. Doctors started to find links between cigarette smoking and diseases like lung cancer. In 1964, the Surgeon General issued its first report on the issue and said ‘yup, these doctors are right.’ Since then, more than 20 million Americans have died from smoking. But people quit too, right? They did. Congress implemented laws to try to keep Americans safe, like requiring cigarette packs to have a health warning on them and banning smoking on flights. That Surgeon General report we just mentioned is estimated to have prevented premature death for 8 million people. Wow. Yup. Meanwhile, scientists have tried to come up with healthier alternatives to smoking. Like, yes, e-cigarettes. The e-cigarettes we have now seem to stem from 1963, when an inventor created a “smokeless non-tobacco cigarette.” Instead of burning tobacco and paper, it heated up liquid that turned into “flavored air” vapor. But manufacturers weren’t interested in making it at the time. What changed? Fast forward to 2003, when a Chinese pharmacist created the modern-day e-cigarette. They became popular in China because they were seen as a way to help quit smoking. Over the next few years, it hit the market in Europe and the US. As more e-cig makers came on the scene, their products sold like crazy. They were heavily marketed, especially to teenagers. And Americans took up the habit thinking it was healthier than regular cigarettes, since e-cigarettes don’t contain tobacco, which has carcinogens (aka chemicals that can cause cancer). Today, there are e-cigarettes for nicotine, THC (a component in weed that can get you high), and CBD (a component in weed that doesn’t get you high). And how do these devices actually work? There are a few different types, but there are four major components: a cartridge that holds liquid (which contains nicotine, THC, or other chemicals), an atomizer that heats the liquid into a vapor that you inhale, a power source (like a battery), and a mouthpiece. But these devices are causing serious health problems. They may not have tobacco, but they are still extremely addictive, and some contain as much nicotine as an entire pack of cigarettes. Then there’s the fact that since the CDC started tracking deaths this summer, it has reported that 54 people have died from vaping-related lung illnesses – and more than 2,500 have gotten sick from vaping. What’s causing all this? We get into that, the government’s response, and the debate around whether e-cigs should be banned, in theSkimm app. Every week, the app goes deep on a different news topic to give you the context you need to understand what's going on in the world. Download the app now and you get the first week free.