page_title: Nested set
hierarchical_section_title: Nested set
caption_attribution_description: English: Logical relationship between taxonomic categories: species, genus, family, order
context_page_description: In a naive set theory, a nested set is a set containing a chain of subsets, forming a hierarchical structure, like Russian dolls.
  It is used as reference-concept in all scientific hierarchy definitions, and many technical approaches, like the tree in computational data structures or nested set model of relational databases.
  Sometimes the concept is confused with a "set of sets" with a hereditary property.
context_section_description: In a naive set theory, a nested set is a set containing a chain of subsets, forming a hierarchical structure, like Russian dolls. 
  It is used as reference-concept in all scientific hierarchy definitions, and many technical approaches, like the tree in computational data structures or nested set model of relational databases.
  Sometimes the concept is confused with a "set of sets" with a hereditary property (like the finiteness in a hereditarily finite set).
caption: Nested set representing a biological taxonomy example. Outside-in: order, family, genus, species.
exif: {}