What does "monochrome laser" mean in Samsung SCX-4300 multifunction printer?

a href="http://www.samsung.com/in/consumer/pc-peripherals-printer/laser-printer-multifunction/mono-laser-mfp/SCX-4300/XIP/index.idx?pagetype=prd_detail" rel="nofollow"http://www.samsung.com/in/consumer/pc-pe…/a