- Defined by an "#IMPORT"

Dependency Hierarchy
- Ideal design, but not always practical.

Dependency Cycles
- Usually BAD
- Breaks Modularity
- Not necessarily bad between classes in the same package (thats what packages are for)

Tightly Coupled
- 2 entities depend on one another in a close cycle

Loosely Coupled
- Larger Dependency Cycle that may include more classes

If you're curious, try:
Class Dependency Analyzer
This tool goes through your code and illustrates your dependency structure. It also shows you where the best points are to break a dependency.