"Who Let the Dogs Out" is the signature chorus of the Baha Men single released in 2000. The song became a mainstream hit that year and spread widely through radio, sports arenas, TV appearances and internet comedy clips. Online, people kept reusing the hook because it instantly signals rowdy energy, animal jokes and out-of-control group moments. It remains popular in short edits and reaction videos for the same reason other instantly readable meme sounds, like badum tss, stay in circulation for years.