That depends on the type of printer. Many modern printers have a built-in ethernet interface, and some of the newest offer WiFi or BlueTooth; you don't actually need to plug in in order to print.
For more common home laser printers, you'll need to either get a print spooler (which is sometimes built into your network switch or your gateway router) or connect to a host PC and then share the printer.
That would be a network printer.
No, it does not have to be. You can make it accessible in wireless network if you connect it to one of computers working in that network. Some routers have on board print servers it makes possible connecting your printer directly to router (via USB).
A local printer is one that is connected directly to an end user's desktop or laptop computer, and is usually used exclusively by that one end user. This is in contrast to a networked printer, which can be accessed and used by multiple people on the same network that the printer is attached to.
A network printer is shared by more than one computer. A local printer is directly connected to one computer. But the printer can be set up as a local or a network printer.
If your printer is attached directly to your computer, you should share it (the way you do it depends of your operating system). If your printer is connected directly to your network (WiFi or Ethernet) it should be properly configured.
If you connect directly to the server, server's memory will be used to spool documents to print. It will allow you to send more print jobs in the same time.
A USB printer is connected to a computer or network by a USB cable - so the answer is "No!"
Mobile photo printers are very useful. The main feature is that by connecting the camera to the printer it will directly print the photo without connecting it to a computer.
It's called "network printer". Such printers usually have either wireless or LAN interface.
connecting directly to a vista computer
Connect your printer to one of computers, and share it for all computers in your network. Or if your printer has its own network interface, connect it directly to the router and use it (you might have to configure it for your network settings).
There are different kinds of printers. Some of them can be connected directly to network. If you have one of them just to that and then using ip address or name of your printer connect to it. If your printer cannot be connect directly to network, connect to your desktop and in the printer's properties choose share. After that check your network environment for shared printers, when you see what you are looking for double click on it, and you are all set.