What does Virtual Printer mean?
A virtual printer is a printer driver that resembles the functionalities of a physical printer, but is not actually associated with one. Instead, a virtual printer sends its output to a file, normally in PDF format or in other image formats like JPEG, TIFF or PostScript.
Techopedia explains Virtual Printer
A virtual printer acts similarly to a physical printer in that it transforms an electronic document into a form that can be easily read by the target user or device. For example, it can transform a spreadsheet or a word processing document into PDF or an image to allow a user to view the document without using the original program that created the document, as these formats are more common. A virtual printer can also be used to send documents to a fax server.
This type of application is also widely used in testing printers because it is cheaper to test the printer output when it is a file than to use paper and ink and to wait for the printout to finish, thus avoiding wastage of resources and energy. Virtual printers made specifically for this purpose can output a result that contains all the layers of a printed image, so an output image has layers of cyan, magenta, yellow and black. The tester can then check the images to find errors in the way that a printer driver or printer firmware creates an image.