Usage of "Kumusta ka/po"
Po is a term that is used to show respect. That is why:
- "Kumusta ka?" is INFORMAL and is used among
friends or when addressing a younger
person.
- "Kumusta po" or "Kumusta ka po?" is FORMAL and is used when addressing an older person. In fact, the best way to say it is "Kumusta po kayo?" using the formal/plural you (kayo) instead of the informal/singular you (ka).
- "Kamusta" is a
popular but wrong way of spelling "kumusta."