The Dunning-Kruger effect is a cognitive bias where individuals with low ability at a task overestimate their competence. This phenomenon occurs because they lack the skills to recognize their own shortcomings, leading to inflated self-assessments. As a result, they may feel more confident than those who are actually more skilled. Conversely, highly skilled individuals may underestimate their abilities, assuming that tasks that are easy for them are also easy for others. This can lead to a lack of confidence in their skills. The effect highlights the importance of self-awareness and the challenges of accurately assessing one's own knowledge and abilities.