Catalysts are essential for several reasons: 1. Increased Reaction Rates: Catalysts lower the activation energy required for the reaction to proceed, significantly speeding up the reaction. 2. Selectivity: Catalysts can be designed to favor the formation of one product over others, thereby increasing the yield of the desired compound. 3. Energy Efficiency: By lowering the activation energy, catalysts can reduce the energy required for reactions, making processes more sustainable and cost-effective.