The concept of 'cognitive load' refers to the total amount of mental effort being used in the working memory. In educational psychology, cognitive load theory suggests that learning is most effective when instructional materials are designed to minimize extraneous cognitive load, thereby freeing resources for schema construction. However, recent research indicates that a certain level of desirable difficulty, such as interleaving practice or introducing occasional spacing, can enhance long-term retention despite increasing intrinsic load. This paradox challenges the simplistic assumption that lower load always leads to better outcomes, implying that the optimal level of load depends on the learner's expertise and the complexity of the task.