1. To send arguments to a method and use those arguments inside the method.

a. How do we write methods with listed parameters.

b. How do we send the arguments to the method.

c. The difference between parameters and arguments.

2. To know when to use parameters.

a. If you are writing a method that does the same exact thing, like a welcome message, then parameters are generally not needed.

b. If you're writing a method that changes, like the quadratic formula, that'll need a different a, b, and c value, then parameters are super helpful.

3. To know that parameters are copies of the values, but not actual access to the variable.

a. When you pass an argument, you are sending a copy of the information.

What is it?

Parameters are a list of variables in a method header; it sets the type and name of a variable that your method can receive and use. They are written inside of the parentheses in the method header.

public static void myMethod(int a, String b, boolean c) {}

Arguments are the actual values that are passed into the method when it is called or invoked.

myMethod(3, "Hi", true); 

Parameters define what a method will accept at run time, arguments are what you actually send to the method. Therefore, parameters are in the method header, but info sent is arguments.

How do we use it?

Crucial Information: If you write parameters, in order to call that method your arguments have to match your parameters. You cannot write a method with two parameters and send it one. They have to match!

Tip: You can put no parameters, one parameter, or many parameters of different types. The choice is yours.

Why/When do we use it?

To write methods that can receive information to be used in the method.

In the previous lesson, if you created a variable in main, you could not use it in your method.

Parameters allow us to share information gathered in one method with other methods!