In the hierarchical data model, entities (for instance, speakers, recordings, or types of speech) are considered as record types. Record types are subdivided into fields. A record stores the information of one particular entity.
Record types are organised in hierarchical tree structures. Except for the topmost record type (the root), each record type in the tree, a node, has exactly one predecessor, and zero or more successor record types. A node with zero successors is a leaf. A record belongs to exactly one record type, and it may be linked to zero or more records in the successor record types.
The hierarchical data model thus considers all relationships between entities as 1:N relationships. Access to record types is possible by navigation through the tree, starting at the root; records are selected from the set of records of a record type.