What is the main difference between a standalone computer and a computer networked via a LAN?

In general, desktop PC is to meet personal (mostly gaming and Home Theater purpose) usage while workstation is definitely for work. Sometimes workstation is designed only to perform 1 function (stock trader workstations don't have CD drives, speakers, or usb ports....only keyboard/mouse/monitor).

Remember though, people sometimes call the same configuration computer at home as "PC" while the one at work is labeled as "workstation"!