The HP EWS 3390 Windows driver refers to a driver package for a printer or multi-function device, specifically the HP LaserJet Enterprise MFP M3390 or similar model, part of HP's LaserJet Enterprise series. EWS typically stands for Embedded Web Server, which is a feature found in many HP printers and multifunction devices that allows you to manage the device remotely through a web interface.

The HP EWS 3390 driver you're referring to may be part of the software package used to enable communication between your Windows computer and the HP LaserJet Enterprise printer, allowing it to print, scan, and perform other functions, as well as access the printer's web interface (EWS) for administrative control.