Abstract: Disclosed are various embodiments for identifying related collections of items within an item universe. Related collections of items can be identified based upon title similarity or a degree of overlap between collections of items. Additionally, relationships between collections of items can be generated if the collections have identical or nearly identical collection titles.

Abstract: A wide variety of content is available for consumption by users on the Internet. Access to this content is facilitated by providing a system to convert at least a portion of this content and distribute the converted content to one or more reader devices. The converted content is configured for presentation on the one or more reader devices. The conversion process may be initiated by a conversion control presented with the content and activated by a user.

Abstract: Disclosed are various embodiments for identifying related collections of items within an item universe. Related collections of items can be identified based upon title similarity or a degree of overlap between collections of items. Additionally, relationships between collections of items can be generated if the collections have identical or nearly identical collection titles.

Abstract: A multi-tiered encryption system efficiently regulates the use of encryption keys to encrypt and decrypt data. The system can include one or more encryption tiers. Each encryption tier can include a computing node programmed to service encryption and/or decryption requests and a key store to store encryption keys. At a root encryption tier, an unencrypted root encryption key can be stored in the key store. Each subsequent encryption tier includes encryption keys that are encrypted by encryption keys stored at a lower encryption tier. The encryption tiers collectively implement an encryption policy in which keys are automatically created and rotated such that a requesting device can request encryption services from the multi-tiered encryption system and receive the encryption services independent of key creation or key rotation and without access to the unencrypted root encryption key.

Abstract: The present disclosure provides a system and methods for intelligently optimizing search system resource usage and performance using multiple data store technologies. A search query optimization system may utilize multiple query processors, such as a general search engine and one or more specialized data stores, to efficiently and intelligently manage and route queries. The search query optimization system may be configured to evaluate the performance of the various query processors for various types of queries, and may use this information to intelligently route search queries to the query processors best suited to service them.