*i want to copy some doc items from one doc library to another document library programatically .I am able to achieve this on my server . But the problem is ,when i want to transfer the doc items from one server to another server programatically . how can this be done*
You may find this link useful if you want to copy it using web service.
I assume by "one server to another server" you mean from one farm to another farm? In any case, consider using the Web Services for this.