The MacBook family were initially housed in designs similar to the iBook and PowerBook lines which preceded them, now making use of a unibody aluminum construction first introduced with the MacBook Air. This new construction also has a black plastic keyboard that was first used on the MacBook Air, which itself was inspired by the sunken keyboard of the original polycarbonate MacBooks. The now standardized keyboard brings congruity to the MacBook line, with black keys on a metallic aluminum body.