Dictionary in C#

Category	Features	Name Space	Inherits from
IDictionary	1.      IDictionary implementations fall into three categories: read-only, fixed-size, variable-size.	System.Collections	ICollection
IDictionary<TKey, TValue>	1.      The IDictionary<TKey, TValue> interface is the base interface for generic collections of key/value pairs. 2.      IDictionary is a "more generic" type .	System.Collections.Generic	ICollection<KeyValuePair<TKey, TValue>
Dictionary	This implementation does not provide a synchronized (thread-safe) wrapper for a DictionaryBase, but derived classes can create their own synchronized versions. Solution: Lock collection to avoid changes made by other threads	System.Collections	IDictionary
Dictionary<TKey, TValue>	1.      Provides a mapping from a set of keys to a set of values. 2.      Retrieving a value by using its key is very fast because class is implemented as a hash table. 3.      A Dictionary<TKey, TValue> can support multiple readers concurrently, as long as the collection is not modified.	System.Collections.Generic	IDictionary<TKey, TValue>