Animation depicting a surface's orientation based on its normal vectors and a "gear and conveyor belt" analogy for the right-hand rule applied to its boundaries.
<a href="//commons.wikimedia.org/wiki/User:LucasVB" title="User:LucasVB">Lucas Vieira</a>
2012-08-13
<span class="int-own-work" lang="en">Own work</span>