Spanish Greetings - Hola

Most people are generally polite and wish to make a good impression - in English we have numerous ways of expressing greetings, some formal, some slang. As one might expect Spanish is similiar, and you're probably well practiced in the standard "buenos días" and "buenas tardes" along with the perfuctory exchanges, "¿Cómo está?" followed by "Muy bien, gracias". So what else can you say? What's the equivilant of "How's it going? Here's a brief list of the other things you can safely say, particulary to those you see more than once in your life.

• "¿Cómo estás?" is the tu form of How are you. Right, you knew this.
  
• "¿Cómo le va?" How's it going? or try the more familiar, "¿Cómo te va?"
  
• "¿Cómo estamos?" How are we?
  
• "¿Qué tal?" What's up?
  
• "¿Qué hay?" or "¿Qué pasa?" What's happening?
  
• "¿Qué hubo?" and "¿Qué onda?" How's it going? and What's happening? Mexico
  

Next post we'll order greeting in a hierarchy of ascending formality.