Groups vs. Tags

Groups

Each node corresponds to an exclusive category:

A1
- B1
  - C1
  - C2
  - C3
- B2
- B3
  - C4
  - C5

Groups with span

A1
- B1
  - C1
  - C2
  - C3
- B2
- B3
  - C4
  - C5

Tags

Each node corresponds to a set of tags:

A, C, E
- A
  - A, D
  - A, D
  - A, D
- B
- C