01_datatypes.md

01 — Data types & variables

Overview

• Primitive types: int, double, boolean, char, long, short, byte, float.
• Reference types: String, arrays, and objects (instances of classes).
• Variables hold values; each variable has a type that determines what it can store.
• Use final for constants.

Common gotchas

• String is immutable.
• Numeric literal types: add L for long, f for float.
• Integer division truncates (e.g., 3/2 == 1). Use 3.0/2 for floating division.

Example: DatatypesExample.java

• Demonstrates declarations, assignment, constants, and type conversion.