The difference between hash table and dictionary in C#

Hash tables and dictionaries are both data structure types used to store data. Both data structures store data in the form of key-value pairs.

Based on the difference between their key features, we can distinguish HashTable and Dictionary as follows-

Sr. Number	Key	Hash table	Dictionary
1	Dictionary
1 td>	Definition	HashTable is a non-generic collection used to store data in the form of key/value pairs, defined in System.Collections in the namespace.	On the other hand, Dictionary is a collection of generic types defined under the System.Collection.Generics namespace, which also stores data in the form of key/value pairs.
2	DataType	In HashTable, data of the same or different data types can be stored as keys and values, there is no limit to what keys and values ​​must Identical data types can only be stored in hash tables. There is also no need to specify the key and value types.	On the other hand, dictionary keys and values ​​can only be stored in a dictionary if they must have the same data type, and the type of the dictionary must be specified when the keys and values ​​are created.
3	Data retrieval	For HashTable, data retrieval is slower due to boxing and unboxing compared to the dictionary.	On the other hand, in case of dictionary, retrieval is faster because no boxing and unboxing is done in case of dictionary.
4	null value	If HashTable null value is accessed to handle a key that does not exist in the given HashTable, then null value is returned as the result .	On the other hand, in case of a dictionary, if you try to access a key that does not exist in the given dictionary, you will get an error.
5	Data order	HashTable does not maintain any order in which key value data is inserted.	On the other hand, Dictionary maintains the insertion order of stored values.

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