From the introduction:
The District is a Post-Apocalyptic RPG set in a very real world after an event, what the event was and how it happened is totally up to you. The core book will cover three cities in North America, Seattle, Chicago and Denver with future sourcebooks covering the rest of the USA, the UK, Europe, Eastern Europe, China, Japan etc.
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The District RPG currently uses a percentile mechanic this means that when you want your character to attempt a task you would roll under their attribute + Skill on a D100.