1. hardwood - the real wood with the stain and the sheen 9usually semi-satin). usually put as raw planks and then - sanded, stained and eurethained (oil or water).can be re-sanded lots of times, restained same or similar color.comes in different woods 9oak, maple, birch, etc) and sizes. standard 3.252. engineered hardwood - bottom - engineered/man-made planks top layer - up to an 0.75-1 inch of real wood stained and eurethained.can be sanded no more than 1-2 times and refinished 9stain can not be changed) by a vERY experienced hardwood installer.laminat - man/made material, on top - plastic thin layer reprint of wood, tile, marble, etc natural material.