This document summarizes absorption costing and marginal costing. Absorption costing treats all manufacturing costs, including both fixed and variable costs, as product costs. Marginal costing treats only variable manufacturing costs as product costs, regarding fixed costs as period costs. Absorption costing follows generally accepted accounting principles but may distort profits, while marginal costing is more relevant for decision making but can manipulate profits. Breakeven analysis uses cost-volume concepts to determine sales needed to cover total costs and achieve a target profit level.