Numbers
Description
byte, short, int, long, float, and double store numbers.
Explanation
int is a common whole-number choice; double is common for measured values.
Example
int score = 95;
double average = 87.5;← Chapter 2 — Core Syntax & Data
7. Primitive Data Types
mixed
Description
Primitive types store simple values directly. Java provides integer, decimal, character, boolean, and byte-sized numeric primitives.
Choose a type that expresses the value clearly. An exam score is usually int, a price often uses BigDecimal in real financial programs, and a yes-or-no answer uses boolean.
Subtopics
char and boolean
Description
char holds one character and boolean holds true or false.
Explanation
A char uses single quotes; a String uses double quotes.
Example
char grade = 'A';
boolean passed = true;Explanation
Each primitive type has a limited range. Selecting long for very large whole numbers and double for fractional values avoids overflow or unwanted truncation.
Example
public class PrimitiveDemo {
public static void main(String[] args) {
int score = 95;
char grade = 'A';
boolean passed = score >= 40;
System.out.println(grade + ": " + passed);
}
}Key points
- Primitives store simple values.
- char uses single quotes.
- boolean is true or false.