Best Answer - Chosen by the Asker
Perhapes, I think it's the only way to say hello in china. “你好”is one of the most popular words in China.
Except it, you can say ZAO SHANG HAO(早上好good moning), XIA WU HAO(下午好Good), WAN SHANG HAO(晚上好good evening) or HEN GAO XING JIAN DAO NI(很高兴见到你nice to meet you) for greeting