An equation that relates reaction rate with concentrations or pressures of reactants and constant parameters (normally rate coefficients). It’s like having a recipe for how fast you can bake those cookies based on how much flour, sugar etc., you have on hand.
Order Of Reaction: This term describes how changing one species' concentration affects overall reaction speed. Like if adding more chocolate chips makes cookie baking go faster, then we'd say it has high order in the reaction.
The time required for a quantity to reduce to half its initial value. It's like if you started eating your cookies and noticed that every hour, about half of them were gone.