Indexing just like in general terms is the use of identity elements in a way that makes locating resources faster or easier.
Take the arrangement of books in an alphabetical order, this certainly makes finding a book by title very easy.
In computing indexing is used in different types of data structures, such as tables [→].
The type of indexing technique used will depend a lot on the data structure itself.
For example, for hash tables hashing algorithms are used to convert the keys to memory locations in other to decide where to store data and later to retrieve it.
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