What exactly is Token? A string of numbers that connects AI fees and memory

This video will use the metaphor of toll booths and Lego bricks to explain in one breath what Token is. I will explain why large models cut text into numbers that you can’t understand, how these numbers become billing units, and how the “memory ceiling” of the model is stuck by the number of Tokens. After reading it, you will understand that Token actually plays three roles at the same time: a translator, which turns the physical world into mathematical symbols; a unit of measurement, which determines the cost of each call to intelligence; and a wall, which delimits how much information the model can remember at that moment. This is the underlying logic of generative AI. Next time you open the dialog box, you will see the token flowing behind the text.