A customer smokes Philip Morris International Inc.'s IQOS smokeless tobacco device at IQOS Store Ginza in Tokyo, Japan, on Monday, June 26, 2017. Akio Kon | Bloomberg | Getty Images

Philip Morris International is seeking approval from the Food and Drug Administration to sell iQOS, a heat-not-burn tobacco product. An independent advisory committee voted Thursday on whether evidence supports PMI's claims, such as that it cuts the risk for tobacco-related disease. The meeting is part of a process to market iQOS as being less risky than cigarettes. If this all sounds like a foreign language, here are the basics.

What are heat-not-burn tobacco products?

As the name suggests, they heat tobacco but don't burn them. Igniting tobacco causes it to undergo a chemical process that emits toxins in cigarettes. Unlike e-cigarettes, which use nicotine-laced liquid, heat-not-burn products use real tobacco. They warm tobacco sticks to a temperature that's high enough to release an aerosol but not enough to cause combustion.They may significantly reduce risk while satisfying users' nicotine cravings. Philip Morris has already launched iQOS in more than 30 markets. Rival British American Tobacco's version, glo, is available in six markets. The company plans to file a substantial equivalence application, a less onerous process, for glo to the FDA this year.

How does iQOS work?

The iQOS tobacco heating system contains three parts: a holder, tobacco stick and a charger. The pen-like device contains a ceramic and gold plate that heats Philip Morris-branded tobacco sticks up to 350 degrees Celsius. Tobacco in cigarettes burns at temperatures at or greater than 600 degrees Celsius. The tobacco sticks are designed specifically for the device. In the U.S., PMI wants to offer Marlboro, Marlboro Smooth Menthol and Marlboro Fresh Menthol HeatSticks. PMI says the product is a closer experience to smoking cigarettes than other alternatives, such as e-cigarettes, because it uses actual tobacco. The company says that could convince adult smokers to switch exclusively to iQOS. Critics point to e-cigarettes being used in addition to and perhaps even leading users into conventional cigarettes. PMI is quick to note iQOS is not an e-cigarette, and the presence of tobacco may not have the same appeal as fruity, sweet nicotine-laced liquid.

Is iQOS safe?

PMI says iQOS is not risk-free, rather it's less risky than conventional cigarettes. The company stresses quitting smoking is the best way to reduce risk and that iQOS is meant for adult smokers who want to continue using tobacco, not kids or non-smokers. PMI has found exclusively using iQOS significantly lowers users' risk of harm than if they were to continue smoking cigarettes. The FDA's review of iQOS identified lower levels of toxic chemicals than cigarettes. It could not say that using the device led to a decreased risk of illnesses associated with smoking because doing so would require a longer study. The FDA will decide whether iQOS can be marketed as being safer than cigarettes.

When might I see iQOS on shelves?