Activity-Based Budgeting (ABB) is a budgeting method where budgets are prepared by identifying and analyzing activities that incur costs in an organization and then allocating resources based on the anticipated performance and necessity of those activities.
Zero-Base Budgeting (ZBB) is a budgeting method where all expenses must be justified for each new period, starting from a 'zero base.' Unlike traditional budgeting, no expenses are automatically carried forward from the previous period.
