These are the two boys Kim plays with in front of the Lahore Museum when he first meets the lama. Chota Lal is a rich Hindu man's son and Abdullah is the child of a Muslim candy-seller. But in spite of the three boys' different racial, religious, and economic backgrounds, Kim, Chota Lal, and Abdullah still play together happily around the giant cannon Zam-Zammah, in front of the museum.
The narrator takes this play as proof that India "is the only democratic land in the world" (1.9). The narrator uses this opening scene between the three kids to show the diversity of India, implying a contrast with the strict class and racial divisions of other nations in this time period.