ThinkPad X1 series

The ThinkPad X1 series is a line of high-end ThinkPad laptop and tablet computers produced by Lenovo. It is a sub-series of the ThinkPad X series designed to be extra premium with material that make them lighter and portable, having been originally classed as Ultrabooks. While the ThinkPad T series is the flagship ThinkPad line, the ThinkPad X1 series's X1 Carbon specifically has been cited as a flagship model since its introduction in 2012.

The current model list contains four product lines:

• X1 Carbon – mainstream premium 14-inch model
• X1 Yoga/2-in-1 – the convertible 14-inch version
• X1 Fold – the first foldable personal computer

Former product lines include:

• X1 Extreme – 15.6-inch (later 16-inch) advanced ultra-light premium laptop; the same model with a Quadro GPU known as ThinkPad P1
• X1 Titanium Yoga – a convertible 13.5-inch version with titanium body
• X1 Nano – a 13.3-inch version – the lightest ThinkPad model