Java-Fundamentals

Hello World in Java

Every programming journey starts with Hello World. Let’s write our first Java program.

The Code

Create a file named HelloWorld.java:

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public class HelloWorld {
    public static …

Variables and Types in Java

Java is a statically typed language, which means every variable must be declared with a specific type before it can be used. The compiler enforces these types at compile time, catching type errors …

Operators in Java

Operators are the workhorses of every Java expression. They combine values, compare them, and update state — and because Java is a statically and strongly typed language, the type of each operand …

Control Flow in Java

Control flow is how a program decides what to do next. Instead of running every line top to bottom, control flow lets your code branch based on conditions and repeat work with loops. Mastering it is …

Functions in Java

In Java, the unit of reusable behavior is the method. Because Java is an object-oriented, class-based language, there are no free-standing functions the way there are in C or Python — every method …

I/O Operations in Java

Input and output (I/O) is how a program talks to the outside world — printing to the terminal, reading what a user types, and persisting data to files. You have already used System.out.println to …