65 ILCS 5/8-2-4

The objects and purposes for which appropriations shall be made in municipalities specified in Section 8-2-1 are classified and standardized by the following items, and by such items shall be designated in the budget document, and the annual appropriation ordinance:

(1) Personal services

(2) Contractual services

(3) Travel

(4) Commodities

(5) Equipment

(6) Permanent improvements

(7) Land

(8) Contingencies

An appropriation in one or more of the items above specified shall be construed in accordance with the definitions and limitations specified in Sections 8-2-1 through 8-2-8, unless the appropriation ordinance otherwise provides. An appropriation for a purpose other than one specified and defined in this section and in Section 8-2-5 may be made only as an additional, separate and distinct item, specifically stating the object and purpose thereof.