手写运算(pen computing)代表的是一种电脑的使用接口，使用平板电脑跟一枝笔（或者触摸笔）作为输入，而不是使用一般的鼠标、键盘、或者摇杆。

实做手写运算的用户接口有好几种方式，实际使用的系统一般会使用里面几种方式的组合

Pen computing refers to a computer user-interface using a pen (or stylus) and tablet, rather than devices such as a keyboard, joysticks or a mouse.

Pen computing is also used to refer to the usage of mobile devices such as wireless tablet PCs, PDAs and GPS receivers. The term has been used to refer to the usage of any product allowing for mobile communication. An indication of such a device is a stylus or digital pen, generally used to press upon a graphics tablet or touchscreen, as opposed to using a more traditional interface such as a keyboard, keypad, mouse or touchpad.