Have you ever had to learn about Venn Diagrams in school and wondered when you might put this logic to use? Or how they might be useful?
Venn diagrams or logic diagrams are used to conceptual logical relations between a collection of different sets or items. Often, circles are used to capture the logical relationships between two or more sets or a collection of items.
Surprisingly, one uses the logical relations depicted by Venn Diagrams regularly. For example, you may be interested in going on holiday and have a list of criteria to help you choose where to go. A house that is within a 15-minute walk to the beach AND restaurants. Or you would like to have a picnic on a lake so are interested in finding a lake that is in a public park that is accessible by car or by bike. Defining these criteria does come in handy when trying to examine and explore topological functions between features or objects. Here are a few examples of different topological functions that might come be useful for comparing features, selecting features, extracting features or attributes associated with features as well as exploring different relationships (overlay, within, proximity).
Many of these operations are available in GIS software packages where you can explore topological relationships between features based on their location but also based on their attributes.
GeoSpatialSense 