Hookahs are water pipes that are used to smoke specially-made tobacco that is usually flavored. Other names are waterpipe, sheesha or shisha. Hookah smoking typically takes place in groups, with the same mouthpiece passed from person to person.
Of those, a majority, or 87 percent, were pro-hookah and included tweets from users and from songs or music. Nearly a quarter were commercial promotions from bars or clubs. Hookah bars are often exempt from indoor-smoking bans enforced in many states and localities, researchers said.