The HP Photosmart C4400 is a series of all-in-one inkjet printers and scanners released by Hewlett-Packard (HP) that includes models like the Photosmart C4480, C4400, and others. These printers typically offer printing, scanning, and copying capabilities, and require specific software and drivers to function properly with Windows computers.

The Windows driver for the HP Photosmart C4400 is the software that allows your printer to communicate with your computer, enabling you to print, scan, and use other features. Without this driver, your computer may not be able to recognize or control the printer correctly.