Exothermic Reaction:A type of chemical reaction that releases energy by light or heat. Like burning wood on a campfire - you start with wood (reactant), it burns (reaction), and you get ash and heat (products).
Endothermic Reaction:This is opposite to exothermic reactions; these reactions absorb energy from their surroundings. Like ice melting - it absorbs heat from its surroundings to transform from solid to liquid form.
Redox Reaction:Short for reduction-oxidation reaction, this involves the transfer of electrons between two species.