WCF Rest service authentication

I am trying to write my first WCF Rest service following

http://msdn.microsoft.com/en-us/library/ee391967%28v=MSDN.10%29.aspx

Sometimes when I go to websites they ask a user to enter a username and password.

I just wanted to know when I'm testing my service with HTTP Get options in a browser, is there a way so that the browser asks for authentication and also how would the WCF rest service get those authentication details.

When you were making the service you must have mentioned the account on which the WCF Service will run (Local account etc). Otherwise you can do it from the service settings for that service. Right click the service, goto logon tab and specify the account you want the service to run. Let me know if that helps