C# HashTable and there uses

C# Hashtable 

The Hashtable in C# is a collection that stores (Keys, Values) pairs.
Here, the Keys are used to find the storage location. A HashTable is
immutable and cannot have duplicate entries. The .Net Framework has
provided a HashTable class that contains all the functionality required
to implement a hashtable without any extra coding.

A hashtable is a general-purpose dictionary collection.
Each item within the collection is a DictionaryEntry object
 with two properties: a key object and a value object.
These are known as Key/Value pairs.
When items are added to a hash table,
a hash code is generated automatically.
This code is hidden from the developer.
All access to the table's values is achieved using the key
object for identification. As the items in the collection
are sorted according to the hidden hash code, the items
should be considered to be randomly ordered.

C# includes Hashtable collection in System.Collections namespace,
which is similar to generic Dictionary collection.
The Hashtable collection stores key-value pairs.
It optimizes lookups by computing the hash code of
 each key and stores it in a different bucket
internally and then matches the hash code of
the specified key at the time of accessing values.