These are labels attached to Posts. They allow you to find related content.

Categories clean power, climate, economics, EU clean power. GB clean power, health, human progress, NEB, plastics, pollution, small actions, transport, waste management

Tags California, China, EfW, GDP, heat, nudge, packaging, rail, reuse, solar, wind.

Many online sources also categorise their content. This screenshot is from The Guardian: you would click on 'PFAS' to see all content with that label. The equivalent Google search is https://www.theguardian.com/environment/pfas.

The Conversation has similar categorisation: see for example articles on microplastics.

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