直线导轨又称线轨、滑轨、线性导轨、线性滑轨，用于直线往复运动场合，且可以承担一定的扭矩，可在高负载的情况下实现高精度的直线运动。在大陆称直线导轨，中国台湾一般称线性导轨，线性滑轨。主要用在自动化机械上比较多,像德国进口的机床,纸碗机,激光焊接机、机床的刀架，拖板等等,当然直线导轨和直线轴是配套用的。

        Linear rail, also known as line rail, slide rail, linear guide rail, linear slide rail, is used in linear reciprocating motion, and can bear certain torque, and can achieve high precision straight line motion in high load condition. In the mainland, it is called linear guide rail. Taiwan is generally called linear guide rail and linear slide rail. It is mainly used in automatic machinery, such as German imported machine tool, paper bowl machine, laser welding machine, tool holder of machine tool, trailing board and so on. Of course, the linear and linear axes are used.