Transformers began as a toy line and animated series in the 1980s, built around robots that disguise themselves as vehicles and other machines, with Optimus Prime as their best-known leader. The transformation noise became one of the franchise's most recognisable audio signatures, instantly signalling a change of form even to people who have not watched every film or episode. Online, short clips of the sound spread through meme pages, edits and soundboards, where creators reuse it far beyond its original scenes. It endures because it is short, instantly readable and funny when applied to everyday transformations.