I am applying to tenure track jobs at high research activity universities in the United State. Wading through open positions, I've become increasingly confused about what is the meaningful distinction between "programs", "institutes", and "departments". I understand faculty are organized into departments, and may participate in multiple institutes or graduate/undergraduate programs. However, for the particular position I am considering, the position is being offered by a particular program, and time is said to be split between the program (0.6FTE) and the appropriate academic department (0.4FTE).
My question is broad. What are the meaningful distinctions between programs, institutes, and departments within a research university?