The Invisible Pink Unicorn (IPU) is a satirical deity used primarily by atheists and skeptics to highlight the logical inconsistencies of theistic claims. Originating in the early 1990s on the alt.atheism Usenet newsgroup, the IPU is defined by the paradoxical attribute of being simultaneously invisible and pink. This concept serves as a rhetorical tool to demonstrate that the burden of proof lies with the person making unfalsifiable claims, similar to Russell's Teapot. In internet culture, the IPU has evolved into a meme used to satirize religious dogmatism and provide a visual representation of how faith can be applied to even the most contradictory or absurd concepts.