1. Core Game
    1. what's the game
    2. how to get started
    3. where to learn more about gameplay
2. Extend
    1. newgrf
    2. AI
    3. GS
    4. playing patchpacks
3. Develop
    1. source
    2. compiling
    3. debugging and troubleshooting
    4. docs 
    5. pull requests
    6. bug reports
    7. feature requests