Excretion is the process by which some of the wastes of the body are already released, while secretion is the process by which there will be movement of some liquids from one place to another in order to fulfill what needs to be done. Some people assume that excretion and secretion are the same, but actually, they are not. It is always important for waste materials to be completely removed from the body because there is a big possibility that the wastes will cause harm, especially when they are not removed immediately. Whenever you feel the need to pee or to pass waste, do it immediately instead of trying to wait.