This meta category should only contain other categories. Files should either be in the relevant subcategory or in the parent category.

English:  Pictures of buildings can be classified like this:

1. Location: see Category:Buildings by country, for example: Category:Buildings in Germany
2. Function: see Category:Buildings by function, for example: Category:factories
3. Style: see Category:Architectural styles, for example: Category:Modern architecture
4. Architect: see Category:Buildings by architect, for example: Category:Buildings by Nicholas Grimshaw