What network is NKN?

Could you elaborate on the nature and purpose of the NKN network? I've heard it mentioned in the cryptocurrency and finance space, but I'm not entirely clear on its specifics. Is NKN a blockchain platform? Does it serve a particular purpose or function in the industry? Could you provide a concise yet comprehensive description of NKN and its place in the broader cryptocurrency ecosystem? Understanding its unique characteristics and value proposition would be greatly appreciated.