What is the difference between KPAs and KPIs?

Based upon an agreed measurement, Key Process Indicators (KPIs) are used for each Key Process Area (KPA) to determine where the organization ranks.

KRA Examples: Strategy, Data Quality, Security
KPI Examples: Has a Strategic plan been created? Is there a Data Quality plan in place? Do security policies meet regulation or compliance?

Each KPA probably has multiple KPIs associated with it. The state of implementation of that KPI will determine where the organization is measured.

Mostly, an aggregation of all the KPIs for a particular KPA determines the final KPA measurement and status.