The sound comes from the Trololo performance by Russian singer Eduard Khil, whose wordless vocal version of a 1966 song resurfaced online around 2009 and exploded in 2010. The old television clip, with Khil smiling and singing trololo syllables instead of lyrics, became a classic rickroll style bait link. People shared it as a joke answer, a troll link, and a reaction to pranks, and the nickname Mr. Trololo stuck. Its cheerful, outdated style is why it still works for internet trolling today.