Final answer:
The Australian Food Composition Database is considered a flat-file database, which is used for simpler and smaller volumes of data without complex querying needs.
Step-by-step explanation:
The Australian Food Composition Database is considered a flat-file database. A flat-file database is a type of database that stores data in a single table. This is contrasted with other complex database structures like relational, hierarchical, and network databases which can hold data in multiple tables and allow for advanced queries and data relationships.
Flat-file databases are typically used for smaller volumes of data that do not require complex queries. They are simpler to understand and can be managed with basic software, but they lack the advanced functionality of more sophisticated database systems.