Objects and Hash tables in JavaScript

Hash tables share many similarities with objects, like storing data in key-value pairs and having the same syntax to add and retrieve elements. We can think of hash tables as a dictionary where you can look up a word definition using just the letter/letters, except for hashing the key string into a series of numbers that will be used to access the value in the array that holds the values.

So in general, we should use hash tables instead of objects because they provide a very fast access to the data stored within.

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Big O Notation

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