Problem solving is a central topic in cognitive psychology because it explains how individuals use mental processes to overcome obstacles and achieve goals. Problems are generally classified into well-defined and ill-defined problems based on the clarity of their goals, rules, and possible solutions. This distinction is important because different types of cognitive processes, strategies, and decision-making mechanisms are required for solving each type. A well-defined problem is one in which the initial state, the goal state, and the operations needed to reach the goal are clearly specified. Such problems have a limited number of possible solutions, and the correctness of the solution can be objectively evaluated. The individual knows exactly what needs to be achieved and the rules that must be followed. Mathematical equations, logic puzzles, crossword puzzles, chess problems, and laboratory tasks are common examples of well-defined problems. In these cases, problem solvers rely on systematic reasoning, algorithms, and step-by-step procedures to reach the correct answer. The cognitive processes involved in solving well-defined problems include identifying the problem, representing it mentally, selecting appropriate strategies, monitoring progress, and evaluating the final solution. Algorithms are particularly effective because they guarantee a correct solution if applied properly. Heuristics, such as means-end analysis, working backward, or divide-and-conquer strategies, may also be used to improve efficiency. Working memory plays an important role in maintaining relevant information, while long-term