1. direct expenses: tied to a specific department or service, vary directly with sales
2. indirect (fixed) expenses: not directly evident in day to day activities (e.g. taxes, rent, etc.)
3. sunk costs: already incurred, cannot be recouped by an alternative
4. differential costs: increase/decrease when comparing alternatives
5. semi-variable costs: both fixed & variable components
6. capital expenditures: major improvements, building, land, large equipment, etc.
7. revenue: total income from sales, services