Federalism differs from a unitary system of governance in that it divides power between central and regional authorities. In a federal system, multiple levels of government exist, each wielding specific powers; for example, both state and federal governments can enact laws. This structure allows for regional autonomy and accommodates diverse needs across different areas. In contrast, a unitary system centralizes authority, with local governments typically operating under the control of the national government, leading to more uniform governance.