The HP copyjet series is a printer cum copier series from the respected brand of HP. It comes with an assurance of smooth and easy printing. It has two printers in its group- HP copyjet with model number C3817A and HP copyjet M with model number C3819A. The series employs thermal inkjet process of operation. The series comprises of printers which have fully fledged printers and can be easily paired up with the computer. Memory expansion is permitted for this series over the standard memory given with the printers. The series is very efficient and gives constant performance.