According to literature like the Principles of Electronic Ceramics by Hench and West, these materials are categorized by how they conduct or resist electric current: Electronic Ceramics - an overview | ScienceDirect Topics

For those interested in learning more about the principles of electronic ceramics, a PDF version of this article can be downloaded from various online sources, including research databases and academic libraries. Additionally, several books and articles on electronic ceramics are available in PDF format, providing in-depth information on the topic.