Methods

A method is a block of code which only runs when it is called.
You can pass data, known as parameters, into a method.
Methods are used to perform certain actions, and they are also known as functions.
Why use methods? To reuse code: define the code once, and use it many times.

Creating a method:-
A method must be declared within a class. It is defined with the name of the method, followed by parentheses ().
Java provides some pre-defined methods, such as System.out.println(),
but you can also create your own methods to perform certain actions
Calling a method:-
To call a method in Java, write the method's name followed by two parentheses () and a semicolon;
public class Main { static void myMethod() { System.out.println("I just got executed!"); } public static void main(String[] args) { myMethod(); } } // Outputs "I just got executed!"

Example Explained
myMethod() is the name of the method
static means that the method belongs to the Main class and not an object of the Main class.
You will learn more about objects and how to access methods through objects later in this tutorial.
void means that this method does not have a return value.

A method can be called multiple times.

Parameters and Arguments:-

Information can be passed to methods as parameter. Parameters act as variables inside the method.
Parameters are specified after the method name, inside the parentheses.
You can add as many parameters as you want, just separate them with a comma.
The following example has a method that takes a String called fname as parameter.
When the method is called, we pass along a first name, which is used inside the method to print the full name
public class Main { static void myMethod(String fname, int age) { System.out.println(fname + " is " + age); } public static void main(String[] args) { myMethod("Liam", 5); myMethod("Jenny", 8); myMethod("Anja", 31); } } // Liam is 5 // Jenny is 8 // Anja is 31

When a parameter is passed to the method, it is called an argument.
So, from the example above: fname is a parameter, while Liam, Jenny and Anja are arguments.

The void keyword, used in the examples above, indicates that the method should not return a value.
If you want the method to return a value, you can use a primitive data type
(such as int, char, etc.) instead of void, and use the return keyword inside the method
public class Main { static int myMethod(int x, int y) { return x + y; } public static void main(String[] args) { int z = myMethod(5, 3); System.out.println(z); } } // Outputs 8 (5 + 3)