How to push data

Hello, I'm a beginner with AD-9361 and NO-OS, so i have some problem. First, I did read all problem in this area but I still don't understand how to create and how to transmit data. I have a module AD-FMCOMMS2 and Zedboard. I see another people ask the same thing like me, Dragos answer that go to config.h and uncoment to DDS generate data but i don't know what is DDS (Sorry!!). So if anybody who understand exactly about how to push or create data, and how to config, please help me step by step, thank you!