Real money balance

Hi guys,

I would like to get more insight on the concept of real money balances.

Correct me if I am wrong: real money balance is the amount of money that individuals have for their daily transactions.

My question was: do real money balances earn any interest? And what it the relation among the quantity of real money balances, interest rates, supply of money, buying governement securities or not to find equilibrium?

Thanks for the help.