meet it

Lines run in order, one after another.

A program can have lots of lines. Java runs them in order, top to bottom, like ticking off a shopping list. Everything your program shows on the screen is called its .

An empty System.out.println() has nothing to show, so you get a blank line. It is handy for spacing things out.

println moves to a new line after showing its text. Its cousin , with no ln, stays on the same line, so the next text carries straight on.

public class Main {
    public static void main(String[] args) {
        System.out.println("Ready");
        System.out.println("Steady");
        System.out.println();
        System.out.print("Go, ");
        System.out.println("go, go!");
    }
}

The ln in println is short for line, so it means print a line.

guess first

How will this look on the screen?

Guess before you run it. Wrong guesses are how you learn, and nothing is marked.

public class Main {
    public static void main(String[] args) {
        System.out.print("Fish ");
        System.out.print("and ");
        System.out.println("chips");
    }
}

your turn

Your turn. Write a knock knock joke.

Type who is at the door on lines 5 and 6, the same both times. Put your punchline on line 8, then press run and enjoy your output.

Your code

output

press run to see what happens

fix it

The cheer is all squashed together. Can you fix it?

Broken code to fix

output

press run to see what happens

Run it and look at the output. Every word lands on the same line.
print stays on the line. Which command moves to a new line afterwards?
Change each print to println, then press run.

nailed it

you made the computer tell a joke. :D

Lines run in order, from top to bottom.
An empty println() makes a blank line.
print stays on the line. println moves to a new one.

new words in your collection

output
print

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