Thermal paste is a substance used to improve the heat transfer between a computer's CPU or GPU and its cooling system. It fills in microscopic gaps and imperfections on the surfaces of these components, ensuring better contact and heat dissipation. This helps prevent overheating and maintains optimal performance. Typically made from a mixture of metal oxides or silicone, thermal paste is applied in a thin layer. It is essential for maintaining the efficiency of cooling solutions like heatsinks and fans. Regularly replacing thermal paste can enhance the longevity and reliability of electronic devices.