Thanks jbalean me and my friends are trying it out but I need another help fo...

Thanks jbalean me and my friends are trying it out but I need another help form you or from anybody who can help. I need to know how CCK provides the default filters for the views module. Meaning when ever we create a content type with CCK fields, CCK automatically provides these fields as filters for the views module. How does it do that, where can I find the code? I have attached a picture showing these fields please check it out to clarify what I mean.