Section 943 - Definitions(a) Function. A function is a group of services aimed at accomplishing a certain purpose or end.(b) Activity. An activity is a specific line of work carried on by a county in order to perform its functions.(c) Budget Unit. A budget unit is that classification of the expenditure and reserve requirements of the Budget into appropriately identified accounting or cost centers deemed necessary or desirable for control of the financial operations. Except as otherwise provided by law, such units may be devised at the discretion of the board.Cal. Code Regs. Tit. 2, § 943