1. One User put  DAML file about user information in his personal webpage.
    He can either create this DAML file using editor like vi, or use following this link.
    Prolog code is here:  
2. The user goto IT-Talk website and register. He inputs DAML file link in his personal webpage,
    so he needn't  input informations which included in his webpage.
    Prolog code is here:  
3. Editor of IT-Talk add a new talk.
     Prolog code is here:  
4. Find all talks which This user  may interested in
    Prolog code is here:1   and here: 2