<a href="https://en.wikipedia.org/wiki/ambigram" class="extiw" title="en:ambigram">Ambigram</a> <a href="https://en.wikipedia.org/wiki/Doug" class="extiw" title="en:Doug"><b>Doug</b></a>, nickname of Douglas. <a href="https://en.wikipedia.org/wiki/Douglas_Hofstadter" class="extiw" title="en:Douglas Hofstadter">Douglas Hofstadter</a> is the person who coined the word "<a href="https://en.wikipedia.org/wiki/ambigram" class="extiw" title="en:ambigram">ambigram</a>". Rotational symmetry of 180 degrees. Created in bold pencil on paper, then vector design. White on black background. Animated GIF.
<a href="//commons.wikimedia.org/wiki/User:Basile_Morin" title="User:Basile Morin">Basile Morin</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>