Sir, What is meant by "Activation Energy"? Getting cofused. Experts please reply me quick please.

Activation energy is the amount of energy that must be provided to the reactants in a chemical reaction to reach a state where they react.Lower is the activation energy, faster is the rate of reaction. For example, striking a match on the side of a matchbox provides the activation energy (in the form of heat produced by friction) necessary for the chemicals in the match to ignite. Activation energy is usually expressed in terms of joules per mole of reactants.