Entity Framework Versus LINQ To SQL (comparison summary)

LINQ to SQL and ADO.NET Entity Framework are extensions of ADO.NET and are introduced to avoid difficulties involved in writing programs using object oriented programming languages to access data residing in RDBMS.

	LINQ To SQL	Entity Framework
Complexity	LINQ To SQL is easier to use.	Entity Framework is more complex compared to LINQ To SQL.
DB Server Support	LINQ To SQL supports only Microsoft SQL Server.	Entity Framework is built on top of ADO.NET data provider model and thus supports all existing ADO.NET data providers  i.e. IBM DB2, Sybase, Oracle, SQL Azure etc.
File Type	It uses Database Markup Language (DBML) file that contains XML mappings of entities to tables.	Entity Framework uses four files EDMX, CSDL, SSDL and MSL. The later three are generated at runtime.
Purpose	Used for rapid application development.	EF is used for enterprise n-tier application.
Coupling	LINQ To SQL is tightly coupled - object property to specific field of database or more correctly object mapping to a specific database schema	EF is loosely coupled.
Model	LINQ To SQL provides one-to-one mapping of tables to classes.	Entity Framework enable decoupling DB Server (Database Schema) and Entity Representation in terms of Model (Conceptual Schema). You can map one table to multiple entities or multiple tables to one entity.
Mapping Type	In LINQ To SQL each table is mapped to single class. Join table must be represented as a class. Also, complex types cannot be easily represented without creating separate table.	In Entity Framework a class can map to multiple tables.
Inheritance	In LINQ To SQL inheritance is difficult to apply. It supports Table Per Class Hierarchy (TPH).	In Entity Framework inheritance is simple to apply. It supports Table Per Class Hierarchy (TPH) and Table Per Type (TPT). It also provides limited support of Table Per Concrete Class (TPC).
Complex Type	LINQ To SQL does not support the creation of complex types.	Entity Framework supports the creation of complex types.
Complexity	LINQ To SQL is simple to learn and implement for Rapid Application Development, but it will not work in complex applications.	Entity Framework has more features which will take time to learn and implement, but it will work in complex applications.
Query Capability	LINQ To SQL has DataContext object through which we can query the database.	With the Entity Framework, we can query database using LINQ To Entities through the ObjectContext object and ESQL (provides SQL like query language). In addition, Entity Framework has ObjectQuery class (used with Object Services for dynamically constructing queries at runtime) and EntityClient provider (runs query against conceptual model).
Performance	LINQ To SQL is slow for the first time run. After first run provides acceptable performance.	Entity Framework is also slow for the first run, but after first run provides slightly better performance compared to LINQ To SQL.
Generate Database from Model	It has no capability to generate database from Model.	Entity Framework supports generation of database from Model.
Future Enhancement	Microsoft intended to obsolete LINQ To SQL after the Entity Framework releases. So it will not receive any future enhancements.	Entity Framework has future enhancements.

So while there is a lot of overlap, LINQ to SQL is targeted more toward rapidly developing applications against your existing Microsoft SQL Server schema, while the Entity Framework provides object- and storage-layer access to Microsoft SQL Server and 3rd party databases through a loosely coupled, flexible mapping to existing relational schema.

For detailed description about EF with sample please check here