Information about named entities referenced in an electronic book (ebook) is provided to a client device. An ebook identifier identifying the ebook is received from the client device. A set of layers available for use with the ebook is determined. The layers in the set provide information associated with the ebook and a layer in the set provides information associated with named entities referenced in content of the ebook. A content range identifying a range of content of the ebook for which layer information is requested and an identification of one or more of the layers in the set for which layer information is requested is received from the client device. Layer information associated with the ebook content identified by the content range for the identified layers is transmitted to the client device. The transmitted layer information includes information associated with named entities referenced by ebook content.