The ThinkPad X series is a line of laptop computers and convertible tablets produced by Lenovo with less power than its other counterparts. It was initially produced by IBM until 2005. IBM announced the ThinkPad X series (initially the X20) in September 2000 with the intention of providing "workers on the move with a better experience in extra-thin and extra-light mobile computing." The ThinkPad X series replaced both the 240 and 570 series during IBM's transition from numbered to letter series during the early 2000s. The first X Series laptops were "slimmer than a deck of cards" and "lighter than a half-gallon of milk", despite the presence of a 12.1-inch Thin-film transistor (TFT LCD) display. These design values—thin and light—continued to be integral to the ThinkPad X-series laptops' d