Data for the returned study material.
For a resource, this is the last time that particular resource was updated.
A unique number identifying the study material.
The kind of object returned.
The URL of the requested resource.
OptionalcodeA resource will never have a code property.
OptionalerrorA resource will never have an error property.
Study materials store user-specific notes and synonyms for a given subject. The records are created as soon as the user enters any study information.
See
https://docs.api.wanikani.com/20170710/#study-materials