Step: 3 Some extended information of the Navigator Pane: 
      Applications-Navigator pane
      

      The application server allows you to configure a server
      
      
      
      
      and so on
      Connecting to Data-Base 10g
      
       
 
      
      
      
      
      
      
      Once you complete the above you will notice that DBConnection1 is 
      appeared under DataBase tree menu.
      