Learning JavaScript Data Structures and Algorithms - Third Edition

Hash table versus hash set

A hash table is the same thing as a hash map. We have covered this data structure in this chapter.

In some programming languages, we also have the hash set implementation. The hash set data structure consists of a set, but to insert, remove, or get elements, we use a hashCode function. We can reuse all the code we implemented in this chapter for a hash set; the difference is that instead of adding a key-value pair, we will insert only the value, not the key. For example, we could use a hash set to store all the English words (without their definitions). Similar to the set data structure, the hash set also stores only unique values, not repeated ones.