Associative arrays are generalized arrays that allow indexing via objects of an arbitrary type (not just integers). Indexers provide a natural notation for associative arrays.
An associative arrays maps a set of objects (the indexing objects, keys) to another set of objects (the element objects).
An example similar to one of the previous indexer examples. In this example it is illustrated how to index via objects of type string.
Associative arrays are in C# implemented by means of hashtables in dictionaries
In the lecture about collections, specifically in the interface IDictionary<K,V> we will see how indexers are can be used to access objects of type V via objects of type K by use of the notation dict[k], where dict is a dictionary and k is a key of type K.