What is Entity Framework and ORM tools

According to Microsoft:
The Microsoft ADO.NET Entity Framework is an Object Relational Mapping that enables to .NET developers to work with relational data as domain-specific objects, eliminating the need for most of the data access plumbing code that developers usually need to write. Using the Entity Framework, developers issue queries using LINQ, then retrieve and manipulate data as strongly typed objects. The Entity Framework's ORM implementation provides services like change tracking, identity resolution, lazy loading, and query translation so that developers can focus on their application-specific business logic rather than the data access fundamentals.
Simply you may say: Entity framework is an Object Relational Mapping tool. It does provide an automated mechanism for accessing & storing the data in the database, and for working with the results, in addition to DataReader and DataSet. 

What is ORM and its need  
ORM is a tool for storing data from domain objects to a relational database like MS SQL Server, in an automated way, without much programming. ORM includes three main parts: Domain class objects, Relational database objects and Mapping information on how domain objects map to relational database objects (tables, views & stored-procedures). ORM allows us to keep our database design separate from our domain class design. This makes the application maintainable and extendable. It also automates standard CRUD operation (Create, Read, Update, and Delete) so that the developer doesn't need to write it manually.

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