What does HI PO stand for?

What does HI PO mean?

HIPO	Hierarchical Input Process Output Academic & Science » Mathematics
HIPO	Hierarchical Input Process Output Computing » General
HI PO	Household International, Inc. Preferred O Business » NYSE Symbols
HIPO	Hierarchy Input Process Output Computing » File Extensions
HIPO	Hierarchy of Input, Processing and Output Governmental » Military
HIPO	Home Improvement Project Opportunities Community
HIPO	Hog International Programmers' Organization Business » Professional Organizations
HIPO	Hierarchical Input/Process Output Governmental » NASA