In the case of traditional ink jet printers, the tiny matchbox size print head moves back and forth.
These movements are one of the reasons for the time lag in the ink jet printing.
While the print head is large enough to cover the whole photo the 5 passes prevents pooling by putting down too much ink at once and enables the printer to hide faulty nozzles.
The Photosmart Express Station is basically a PM1000 print engine with a user friendly kiosk mounted on top designed for customers to print photos quickly from memory cards or other sources.
[2] This enables the printer to print up to 71 pages per minute in black and color (CM8060)[3] and 57 ppm (CM8050).