The num num num sound is an online version of the classic nom nom nom eating vocalisation, written and spoken to imitate happy chewing. Short clips like this spread through meme soundboards, short videos and reaction edits because the meaning is clear even without context or subtitles. Creators use it for food scenes, cute animals, animated characters and ironic posts about snacks that disappear too quickly. Its lasting appeal is simplicity, as three repeated syllables can signal enjoyment, hunger or playful greed in just a few seconds of audio.