Ambigrams are images that spell out a word and that are identical under a discrete transformation, typically a half-cycle rotation. They were invented by Douglas Hofstadter—of Gödel, Escher, Bach fame—and I suspect I first was introduced to ambigrams by the writings of Martin Gardner, perhaps his Aha! Gotcha book that was one of my favorites as a child.
In December 2018 I sketched out my own ambigram using Procreate on an iPad. I finalized the design using Affinty Designer and have since used the design as a personal logo. The design lends itself to vinyl stickers to place on my electronic devices.
My ambigram is not a pure ambigram since the
f and the
p are slightly asymmetric based on which leg goes under the other.