It sells ice cream and sugary drinks for under $1. Its mascot looks like the love child of Frosty the Snowman and the Michelin Man. And its stores relentlessly blare a jingle set to the tune of “Oh! Susanna.

The chain, which has over 45,000 stores worldwide, has attracted customers with cheap ice cream and bubble tea.

When you think about the most famous fast food chains in the world, companies like McDonald’s, Burger King, and Starbucks will likely spring to mind. But you might be surprised to learn that none of these are actually the world’s biggest chain.