Network print servers are an inexpensive and great solution to a common home or office network. Sure you can "share" printers attached to particular machines, but that creates a dependency on that machine being up and running.
With a network print server, that dependency disappears. People on the network can print without a particular machine being on and available.
In home and office networks, it's often desireable to share printers. It saves the expense of each workstation needing its own printer. Printer sharing has been with us so long that we take it for granted.
The biggest problem with traditional printer sharing is that, not only does the printer need to be on, but the workstation to which it's attached has to be up and running - and available on the network. If that workstation has a problem, its printer(s) are "lost" to everybody on the network.
A lesser problem is that, in a high output office, printing duties can affect the host workstation's performance. (Back in the bad old days we addressed that problem by dedicating one machine as a printer server.
A Silver Bullet as Cheap as Lead
Enter a great solution to all of the above: The inexpensive network print server.
A network print server is a compact "appliance" that connects to your network and "serves" one or more printers.
How Does it Work?
Internally, network print servers are "computers" in their own right. They typically run a small version of the Linux operating system optimized for networking and printing.
They also provide a device management utility, usually in the form of a web application so the print server can be managed by any computer on the network that has a web browser. (Virtually all network print servers provide for "administrator" security by user name and password.)
Because most modern printers have USB ports, most network print servers provide one or more USB ports.
Another Problem They Solve
I have an old but perfectly serviceable workhorse of a printer, a Hewlett-Packard Laseret 4 Plus. I love it because it just keeps working and working; and its output looks as good as brand new models. Problem: That old Laserjet has only a parallel port and most newer computers have abandoned the parallel port altogether. My newer workstations are like that; gobs of USB ports, but not a single parallel port in sight.
That problem is solved by my print server. It has a parallel port, so I can keep using that old Laserjet until it goes up in smoke (I don't think it ever will).
So How Big Are These Appliances?
Size is almost a non-factor. I've seen network print servers no larger than a pack of cigarettes. Fuller-featured models are about the size of a network switch or hub. Mine is about 5 by 6 by 1 inches and is attached to the underside of my desk with a couple strips of adhesive-backed Velcro. It's powered by a typical wall-wart.
What Do They Cost?
Great question; I'm glad you asked. I just did a quick Google search and found one refurbished unit selling for $14! Depending on your needs, though, you'll probably pay a little more - but not much more.
Say you want to share just two USB printers on your network. Drilling into my search results, I found models as low as $17 but more typically about $25.
Say you want to share one printer with a parallel port and two USB printers. That costs a little more; a quick search found one selling for $54. Trolling ebay would probably find better deals, especially if you aren't bothered by used items. (When an electronics device has no moving parts (and print servers don't), I'm not bothered at all about the item being used.)
Do I Need a Rocket Scientist to Install and Configure a Print Server?
Absolutely not! If you select a unit from a reputable maker, and if you can follow simple instructions, it's almost a no-brainer. As a boon, both modern Windows operating systems and Mac operating systems make networking tasks a breeze.
Are There Alternatives?
Yes. Quite a few of the "upper tier" printers come with an Ethernet port. They connect to your network instead of to a single workstion, so they act pretty much like a "one port network print server." Many of these are fine printers, but are often considerably more costly than their USB-only brethern.
Do you have more than one printer to share? Or do you have an older printer with only a parallel port, but a computer without a parallel port? Or do you have one expensive laser printer you'd like to share instead of buying printers for each workstation on your network? Or do you have some combination of these needs?
If you answered "yes" to any of the above, what are you waiting for? Get a network print server; the return on that small investment will be realized soon - and many times over.