Usually, you simply print from your text editor to a printer.
PrinterShare allows you to create virtual copy of a printer attached to another computer. Your text editor will not know about this substitution and will print as usual. Then the virtual printer will send the document over the Internet to another machine.
Note that the document is not sent directly to real printer. It is sent to the PrinterShare client. The client works like mailbox. You can set it up to hold the incoming documents until you are ready to review and print them, or to print automatically.
Mobile devices, such as iPhone or Android phones, have no idea about printers and do not provide you "Print" option in applications. However, mobile PrinterShare client can access data on the device, package it as a printable document, and send for printing.
Some mobile PrinterShare clients are also capable of printing directly on stand-alone WiFi printers. This is an exceptional case, when document is sent to printer itself, and not to another PrinterShare client. Not all WiFi printers are supported.
Shared Printers represent Real Printers in PrinterShare network. When you are looking for a printer to print on, you don't see Real Printers, you only see Shared Printers.
Of course, it is not necessary to create a Shared Printer for every Real Printer connected to your machine.
Shared Printer is maintained by PrinterShare client running on desktop computer connected to the Real Printer. If PrinterShare client is not running, Shared Printer is offline.
If shared printer is online, printed document is uploaded directly to target machine. It is fast and secure. So, normally you want to keep your printers online.
If shared printer is offline, you still can print on it. The document will be temporarily stored on PrinterShare print server, and downloaded by receiving client as soon as it will be ready.
Not all PrinterShare clients support direct transfer. Some of them always use server-storage method, because it is simplier. You should not worry about it - there's no practical difference between the two methods, except delivery speed.