• Key-Value Store - Stores simple or complex data by a single key
• Relational - Organize data into tables. Access via SQL
  • These were the gold standard. Very flexible and safe
  • Cross-references multiple tables for complex data
  • Complex queries are expensive. May not scale to huge sizes
• Document Databases - Stores data in documents. No cross-references
  • Less flexible but can scale larger in some cases
  • Easier for some types of apps. Hard to adapt
• Graph Database - Thinks about data in graphs. Good for very connected data

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