Module 2: Output, Input, Variables, and Types

Printing Text and Numbers with `System.out.println`

Use console output to display strings, numbers, and quick feedback while you learn.

Author

Java Learner Editorial Team

Reviewer

Technical review by Java Learner

Last reviewed

2026-04-16

Java version

Java 25 LTS

How this lesson was prepared: AI-assisted draft, edited by hand, and checked against current Java 25 documentation and runnable examples.

Learning goals

Print text and numbers clearly
See the difference between plain text and calculated output
Use output as a simple debugging tool

Why this matters: Output is how you see what your program is doing. Early on, printing values is also your fastest debugging technique.

Strings vs numbers: Text goes in double quotes, but numbers do not. System.out.println("5") prints a string, while System.out.println(5) prints a number.

You can print expressions too: Java evaluates expressions before printing them, so System.out.println(2 + 3) prints 5.

Good habit: Print small checkpoints while learning so you can see program state change line by line.

Runnable examples

Print text and a number

public class Main {
    public static void main(String[] args) {
        System.out.println("Java practice");
        System.out.println(25);
    }
}

Expected output

Java practice
25

Print a calculation

public class Main {
    public static void main(String[] args) {
        System.out.println(7 + 4);
        System.out.println("Total: " + 11);
    }
}

Expected output

11
Total: 11

Common mistakes

Using quotes around a number you want to calculate with

Keep numbers unquoted when they are meant to be numeric values.

Mini exercise

Print your age on one line and the sum of 8 + 5 on the next line.

Summary

Printing is your first feedback loop.
Java can print both text and evaluated expressions.

Next step

Now that you can print values, you need a place to store them: variables.

Sources used

Printing Text and Numbers with `System.out.println`

Print text and a number

Print a calculation

What does `System.out.println(2 + 3)` print?