The app, which was launched world-wide in October, is modeled on Wordpress, and is intended to allow people to create anonymous chat forums on any subject they like.
The rooms allow the exchange of chat, images and video, and can be heavily customized.
The system is not currently integrated with Facebook, which means you can login with any name you want--including different screen names on different forums.
Rooms can also be made adult-only by restricting access to people 18-years-or-older.
There are plans for the launch of an Android version of the app, but no date has yet been announced.
Rooms can be created by anyone, and are expected to offer an experience similar to Reddit.
Old-timers may remember the years of Bulletin Board Systems (BBS) and Compuserve which offered similar capabilities.
Many of those old systems were supplanted by the arrival of Facebook, which has dominated the global Internet personal communication market, outside of Russia and China, who have their own versions.
Now Facebook has launched Rooms after acquiring a startup in January, which it believes addresses a clear gap in the market.
According to their spokesman Josh Miller, users must use their real name when first installing the app. He added that images will be checked by software for pornography, which will be deleted.
In addition, specific combinations of words associated with threats or violence may also be deleted, but otherwise users would moderate their own rooms, he said.