The system is quite flexible when it comes to printing. The standard print request window enables you to print to any available printer, but also to email and preview the document. If you request a preview, the pdf file will be downloaded to your browser from where you can save it or print it.
For many documents, ie invoices, receipts, etc, the system maintains a 'Printed' flag. If set it means that someone has printed the item. However, note that previewing or emailing it does not count as printing.
The administrator can set a default printer for each practice location using Administration|Organisation|Practice Location.
It is also possible to set a default printer for each type of document. More correctly, you can specify the default printer for each document template - see Administration|Templates. You can also set the document to print to a specific printer without displaying the print request window. This is useful with dispensing labels where you always want these printed on the label printer rather than on a standard printer.
These templates also allow flexible control of when documents are printed - see the above link.
Note that these printers are the printers that are available to the server running the database and application. Unless you are running everything on your own machine, the server's printers may be different from your own. If the server has no printers then you can still print - a pdf will be generated and downloaded just as though you pressed the Preview button.
If you have a situation in which your office is split over two floors and you want different default label and standard printers for each floor, then you can accomplish this as follows:
Note that if you are using reports that report stuff by practice location, you will need to combine the the information for Main-Upstairs and Main-Downstairs in order to get the totals for the Main location.