A hand-held, button-activated input device that when rolled along a flat surface directs an indicator to move correspondingly about a computer screen, allowing the operator to move the indicator freely, as to select operations or manipulate text or graphics.鼠标一种手用的、用按扭控制的输入设备,当在平台上滑动时可以相应地移动计算机屏幕上的指示箭头,使得操作者可以随意控制指示箭头,由此来选择项目、控制内容或作图