Decisions are an assumption of ration behavior. People assume people will try to maximize benefits and minimize cost. For example, they will maximize happiness, well being, satisfaction, etc..
Some examples of choice is the cost of one more plate while eating out, you would get more, and have to pay more. Another example is your benefits from taking or not taking a class
Information : You use information everyday in life, and no, it is not free, but knowing information helps you choice your decisions and determines the cost.