program. The program don't store any data. We store data in the account owned by the program. In Solana, every account has a program as an owner. Only the owner can modify the account's data. Takes the token program as an example. You will create an account belongs to the token program and you will transfer token in the token program. The token account will store your balance back to the account it owned.
getMinimumBalanceForRentExemptionto get the number.