What do `i` and `Number` represent in the Bakery Algorithm?
As the Wikipedia page says, (emphasis mine),


  Lamport envisioned a bakery with a numbering machine at its entrance so each customer is given a unique number. Numbers increase by one as customers enter the store. A global counter displays the number of the customer that is currently being served. All other customers must wait in a queue until the baker finishes serving the current customer and the next number is displayed. When the customer is done shopping and has disposed of his or her number, the clerk increments the number, allowing the next customer to be served. That customer must draw another number from the numbering machine in order to shop again.
  
  According to the analogy, the "customers" are threads, identified by the letter i, obtained from a global variable.