text: please i need a detail explanation on  linux and unix operating systems? 1.i,m running a cybercafe with 15 computers.i wish to know how to run and schedule my prevetive maintenance scheme such that my pcs are always in tact.2.i want to setup internet in an office with 4 pcs using dial up.i have a 6port switch an external modem,one of the pcs will be the server.win2000 is install in all pcs.at this point how do i go ahead with the setup ,considering the ip addresses gateway and dns servers configrations linux is a free os, you can find some tutorials on how to set up  a network on the links.  you'll learn a lot by setting up a linux network, even though nowadays its easier to do than it was 5 yrs ago.