the things that TEZ told you are some ways of saying hello in spanish, but we have others. In Argentina, the place where I live, we say:
*hola: hello
*¿Cómo va todo?: is like saying how is your life going?
*¿Qué contás?/¿Cómo andás?/¿Cómo estás?: how are you?
The differents way of saying hello in Spanish depend on the country and the different cultures. In some Spanish-speaking countries we use some ways of saying hello that are not common in other countries. Moreover, some greetings are not used in Argentina, for example, or are considered oldfashioned or silly(like "QUIUBO")