Banking activities face operational risk, which can be unpredictable and harmful. The economic essence of operational risk lies in its impact on banks, with four main sources identified: people, processes, systems, and external events. Operational risk is complex to assess, measure, and predict, often leading to delayed but significant losses, especially from human error. All sources of operational risk in a bank are interconnected. Future research should focus on learning from past operational risk events to improve risk management. As technology advances, managing operational risk will be crucial for all banks.