What is the difference between hash table and dictionary?

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What is the difference between hash table and dictionary?

The main difference between a hash table and a dictionary is the terminology used and the programming language in which they are implemented.

A hash table is a data structure that uses a hash function to map keys to values. It is commonly used in computer science and is implemented in various programming languages such as C++, Java, and Python. In a hash table, the keys are hashed using a hash function, and the resulting hash value is used as an index to store and retrieve the corresponding value. Hash tables provide efficient lookup, insertion, and deletion operations, typically with an average time complexity of O(1).

On the other hand, a dictionary is a similar concept but is typically used in the context of specific programming languages. For example, in Python, a dictionary is a built-in data type that stores key-value pairs. It is implemented using a hash table internally, but the term "dictionary" is used to refer to this specific implementation in Python. Similarly, other programming languages may have their own terminology for similar data structures, such as "associative array" or "map".

In summary, the main difference between a hash table and a dictionary is that a hash table is a general term for a data structure that uses a hash function to map keys to values, while a dictionary is a specific implementation of a hash table in a particular programming language.