Fourier's law of heat conduction

Fourier’s law of heat conduction states that heat energy flows from a hotter area to a cooler one through a material, and the amount of heat transferred depends on how steep the temperature difference is and the material’s ability to conduct heat. Mathematically, it’s expressed as the heat transfer rate being proportional to the temperature gradient and the material’s thermal conductivity. Essentially, it explains how and why heat moves within objects, such as warming your hands near a fire or cooling a hot cup of coffee, emphasizing that heat moves naturally from warmer to cooler regions.