What are the three types of PHA?

Excuse me, could you please elaborate on the three types of PHA you've mentioned? Are they related to public health, or perhaps a specific area within the cryptocurrency and finance world? If they're in the realm of public health, I'm curious to know if they involve risks, assessments, or perhaps actions. On the other hand, if they're tied to cryptocurrency and finance, I'd be interested in understanding their significance and potential impact on the market. Could you please clarify and provide some context? Thank you in advance.