Editing List of data structures (section)

=== Abstract data types ===
{{main|Abstract data type}}
*[[Container (data structure)|Container]]
*[[List (abstract data type)|List]]
*[[Tuple]]
*[[Associative array|Associative array, Map]]
*[[Multimap]]
*[[Set (abstract data type)|Set]]
*[[Multiset (abstract data type)|Multiset (bag)]]
*[[Stack (abstract data type)|Stack]]
*[[Queue (abstract data type)|Queue]] (example [[Priority queue]])
*[[Double-ended queue]]
*[[Graph (data structure)|Graph]] (example [[Tree (data structure)|Tree]], [[Heap (data structure)|Heap]])

Some properties of abstract data types:
{| class="wikitable"
!Structure
!Ordered?
!Uniqueness?
|-
| [[List (abstract data type)|List]]
| yes
| no
|-
| [[Associative array]]
| no
| keys (indexes) only
|-
| [[Set (abstract data type)|Set]]
| no
| yes
|-
| [[Stack (abstract data type)|Stack]]
| yes
| no
|-
| [[Multimap]]
| no
| no
|-
| [[Multiset (abstract data type)|Multiset (bag)]]
| no
| no
|-
| [[Queue (abstract data type)|Queue]] 
| yes
| no
|}

"Ordered" means that the elements of the data type have some kind of explicit order to them, where an element can be considered "before" or "after" another element. This order is usually determined by the order in which the elements are added to the structure, but the elements can be rearranged in some contexts, such as [[Sorting algorithm|sorting]] a list. For a structure that isn't ordered, on the other hand, no assumptions can be made about the ordering of the elements (although a physical implementation of these data types will often apply some kind of arbitrary ordering). "Uniqueness" means that duplicate elements are not allowed. Depending on the implementation of the data type, attempting to add a duplicate element may either be ignored, overwrite the existing element, or raise an error. The detection for duplicates is based on some inbuilt (or alternatively, user-defined) rule for comparing elements.