Local Storage: Hard DrivesPrimary Data Store: Relational DatabasesReading and Writing DataACID TransactionsSchemas and ConstraintsExample: PostgreSQL, Lambda, and Schema MigrationsCaching: Key-Value Stores and CDNsKey-Value StoresCDNsFile Storage: File Servers and Object StoresFile ServersObject StoresExample: Serving Files with S3 and CloudFrontSemistructured Data and Search: Document StoresReading and Writing DataACID TransactionsSchemas and ConstraintsAnalytics: Columnar DatabasesColumnar Database BasicsAnalytics Use CasesAsynchronous Processing: Queues and StreamsMessage QueuesEvent StreamsScalability and AvailabilityRelational DatabasesNoSQL and NewSQL DatabasesDistributed SystemsBackup and RecoveryBackup StrategiesBackup RecommendationsExample: Backups and Read Replicas with PostgreSQLConclusion