1. GTECH 709 Spatial relationships
Topological relationships .. and their importance

2. Spatial Relationships (1)
Equals
A is the same as B
Touches
A touches B
Overlaps
A and B have multiple points in common
Contains
A contains B

3. Spatial Relationships (2)
Disjoint
A shares nothing with B
Covers
A covers B
Crosses
A and B have at least one point in common B A A B A B

4. Ignore at your Own Risk What would happen if we ignored them?
Mapquest and Google Maps would be useless
Consider 500 road segments of your neighborhood collected with a GPS