Methods can act differently based on the value of the instance variables. You can pass values into your methods. Using the example from the book if you want to control how many times the dog will bark. "d" being the dog, "bark" being the variable, and in the () will be the value of the vairable. so like in the book , d.bark(3) it telling the dog to bark3 times.
Also with methods you can get thins back from them.Every method gets a return type. As well as being to return things from a method you can send more than one thing to a method. Methods have multiple parameters. In order for them to work they have separated by a comma so an example would be t.takeTwo(11, 54)
