Difference between WCF and Web Service

WCF (Windows Communication Foundation): WCF, as the name suggests, is a unified .NET framework that is used to develop service-oriented applications. It allows you to develop applications that can communicate using different communication mechanisms. It is founded for other Microsoft Distributed Technologies and considered the future of distributed computing.  Because of its flexibility, it makes the development of endpoints much easier. It supports various programming languages and platforms. It is SOAP-based and returns data in XML form. It can be hosted in different scenarios, and such scenarios include various services such as WAS, IIS, Managed Windows, etc. The following code will be used to build a service in WCF:  

[ServiceContract]  
public interface ITest  
{    
 [OperationContract]    
 string ShowMessage(string strMsg);  
}  
public class Service: ITest  
{    
 public string ShowMessage(string strMsg)    

Web Service: Web Service, as the name suggests, is a client-server application that allows communication between client and server applications. It is basically a software module specially designed to execute a certain set of tasks. This service is specially used to make application platforms and technology independent. There are two types of web services include the SOAP web services and RESTful web services.  Following code will be used to build a service in Web service: 

[WebService]  
public class Service: System.Web.Services.WebService  
{  
 [WebMethod]  
 public string Test(string strMsg)    
    {    return strMsg; 
    }  
}  

WCF vs Web Service