A Hierarchical Database System organizes data in a tree-like structure, where each record has a single parent and can have multiple children. This model allows for a clear, organized way to represent relationships between data, making it easy to navigate from one record to another. In a hierarchical database, data is accessed through a series of parent-child relationships, which can simplify data retrieval. However, this structure can be rigid, as it does not easily accommodate many-to-many relationships, making it less flexible compared to other database models like relational databases.