Independent symbol in TeX

A friend of mine asked me how to type a independent symbol in Word using the equation editor. I was surprised that there is no such symbol in the equation editor. So I am proud of my self as the TeX user because I thought there must be such a symbol in TeX system. But I was wrong. You need to define it on your own. Luckily, Dr. Donald Knuth has done it. So here is the code:

\newcommand\independent{\protect\mathpalette{\protect\independenT}{\perp}}

\def\independenT#1#2{\mathrel{\rlap{$#1#2$}\mkern2mu{#1#2}}}

As usual, you can use $\independent$ to get the symbol.

For the Word user, here is the gif file for you to copy and paste it in.