Can an asp.net webpage submit information to a webservice written in C#?

 Hi guys,
 I'm new to asp.net.  Basically I'm wondering if this is possible and if it is, where can I find more information about getting it set up?  
Basically the webservice which was written in C# is what interacts with the database.  It will add users, etc.   Once the user types in the information into the website such as a username nad password, I want the webpage to call the webservices functions to pass that information to the webservice and the web service will send that infromation to the database.  Such as username or any other hidden fields.  Is this possible?  I realize it would probably be easier to totally not even deal with the webservice, and submit the information directly to the database from the webpage but this isnt possible, we must use the webservice.
 
Thanks

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