# Catalogues & categories
### What are catalogues
Catalogues are root elements in category structures used for organizing products logically in categories.
### What are categories
Categories are used to create hierarchical structures within a catalogue. Categories serves as a means for structuring products in meaningful classifications.
Categories can be organized in a nested structure to form the desired hierarchical structure. There are no limitations to the number of categories and depth of category structure in the system.
### Standard category
Standard categories allows classifying products and variant groups manually.
### Dynamic category
Dynamic categories allows you to automatically classify products and variant groups, which meet certain criteria.
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