Thermal pads are products used for heat dissipation. The thermal pads are sandwiched between two components and allow heat to be transferred between them. Thermal pads usually consist of a thermally conductive but pressure-resistant layer of silicone or other thermally conductive material that is clamped between two surfaces.
Thermal paste is used to improve heat transfer between a component and a heat dissipation surface. The primary function of thermal paste is to fill microscopic imperfections in the surface structure, replacing trapped heat-insulating air with highly thermally conductive material to improve heat dissipation. It usually consists of a mixture of silicone oil and metal particles that act as heat conductors.
Thermal conductive adhesive is used to attach equipment to a heat dissipation surface. Thermal conductive adhesive consists of a thermally conductive material that is bonded between two components to improve heat transfer.