Computers have names just like people.
You have to tell your Internet program the names of the computers that are used for certain purposes to it will talk to the right one. For the record, POP stands for Post Office Protocol. SMTP stands for Simple Mail Transfer Protocol. NNTP stands for Network News Transfer Protocol. I've made a change to my web pages and installed the new page on Interstice, but when I look at it in Netscape, I still see the old page.