Explain the hierarchical data model

The hierarchical data model organizes data in a tree-like structure with a parent-child relationship. Key points include:

1. **Tree Structure:** Data is arranged in a hierarchy with a single root node and multiple levels of child nodes, resembling a tree.

2. **Parent-Child Relationship:** Each child node has only one parent, but a parent can have multiple children.

3. **Data Retrieval:** Data retrieval follows the hierarchy, requiring traversal from the root to specific child nodes.

4. **Use Cases:** Commonly used in file systems and organizational structures.

The hierarchical model is simple and efficient for certain types of queries but can be rigid and less flexible compared to other data models.