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A proposal for tag hierarchy on SOA proposal for tag hierarchy on SO
Since so many thousands of tags and topics exist, it would be really useful to visually browse through tags by organizing them into a hierarchy, or hierarchical map. This drill-down map would make it easier to find the tag/subtopic you want or just generally browse within the topics you're interested in.
So we could nest all "visual-studio-2008" and "visual-studio-2003" tags into "visual-studio", which would be under "dev-tools". Something like how Wikipedia's categories have sub-categories.