Zen means meditation, not necessarily meditation on any set thing. It can just be ongoing meditation on where the total you--mind, body and life--are at each present moment. That word "sangha" (pronounced "sahng′-hah") means a group that comes together with a purpose in common. So there is an agreement between us to help each other--for instance, by sitting still (within reason) so as not to disturb each other during meditation.
We have no dependency on any other organization, but we have a long-term and strong relation with DBZ (www.daibosatsu.org), Dai Bosatsu Zendo Kongo-ji, a Rinzai Zen Buddhist monastery in New York State. Zenrin, our Zen "teacher," trained there trained there for 12 years with its founding abbot, Eido Tai Shimano Roshi, and now also with its abbot, Shinge Roshi, Roko Sherry Chayat (the title "Roshi" means Zen Master). Their lineage goes back through the 9th Century Chinese Zen Master Rinzai all the way to the Buddha, nearly 2500 years ago. Thus we are able to offer Zen training in the Rinzai tradition here in Jacksonville and, through "scholarships," at DBZ itself.
But you by no means have to be Buddhist or Zen to come and "try it out". A couple of us are Catholics, and another is a Muslim. People come for all sorts of reasons, for instance, as a slow but steady and very effective way to deal with high blood pressure. And zazen (sitting Zen) makes you healthy in general. There's a plus: if you stay with it, you'll find yourself with deeper peace of mind than you have ever known.
We are supported entirely by free-will donations. There is a donation box so they can be anonymous. But we are a tax-exempt corporation, so they can also be tax-deductible, and can even be made online.