What type of costs do salaries and rent fall under?

Salaries and rent are categorized as fixed costs because they do not fluctuate with the level of production or sales volume. Fixed costs are expenses that remain constant regardless of the business's operational activity within a certain range. For instance, regardless of how much product a company produces, it must pay its employees and pay for the office or factory space, making these expenses predictable and stable.

In contrast, variable costs change directly with the level of production. For example, materials and labor that increase with production volume would be considered variable costs. Operational costs refer to the total expenses incurred in the day-to-day functioning of the business and can include both fixed and variable costs. Marginal costs specifically relate to the cost of producing an additional unit of a product, rather than being tied directly to fixed expenses like salaries or rent. Thus, identifying salaries and rent as fixed costs underscores their predictable nature and highlights their importance in financial planning.