# Community directories
Community directories are powerful ways to centralize and share knowledge within a community.
## Description
- Listing a ton of items with details, encyclopedia-style
- Curate and categorize to build sets (per city, per country, etc)
- Next level is to create a comparison engine to show how things can go together or compare/contrast them
- Supplemented by content (articles, videos, etc)
## Types
- Founder maintains it and charges access to the data, curation
- The founder has an audience/community and they charge people to be able to list stuff
- Directory as marketing (e.g., Zapier's app directory)
- Directory for directory
- End up charging to have your product ranked higher (e.g., G2 crowd/capterra)
- Erodes trust in the data over time