Arts & Recreation: Encompasses fine arts, architecture, music, sports, games, and entertainment.

Covers a wide range of topics including General Knowledge, Science, Information Science, Reference Materials

Language: Covers linguistics, grammar, dictionaries, language learning materials, and literature in different languages.

Literature: Covers literature in various languages, literary criticism, poetry, drama, and prose fiction.

Natural Sciences & Mathematics: Encompasses mathematics, astronomy, physics, chemistry, biology, and earth sciences.