DataTypes_Java:)

• In Java, every variable must have a data type.
• A data type tells the compiler what kind of value a variable can store and how much memory it needs.

What is a Data Type?

• A data type is a classification that specifies the type of value a variable can hold.

Types of Data Types in Java:

1)Primitive Data Types
2)Non-Primitive (Reference) Data Types

Primitive Data Types:

• Primitive data types store simple values directly in memory.
• They are predefined by Java and are not objects.
• Java has 8 primitive data types.

1)byte:

• Used to store small whole numbers.
• Size: 1 byte (8 bits)
• Range: -128 to 127.

byte age = 25;

2)short:

• stores slightly larger whole numbers than byte.
• Size: 2 bytes
• Range: -32,768 to 32,767

short year = 2025;

3)int (Most Common Integer Type):

• used to store whole numbers.
• Size: 4 bytes
• Range: -2,147,483,648 to 2,147,483,647

int marks = 95;

4)long:

• stores very large whole numbers.
• Size: 8 bytes
• Range: -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807

long population = 8000000000L;

5)float:

• stores decimal numbers with single precision.
• Size: 4 bytes
• Precision: 6–7 decimal digits

float temperature = 36.5f;

6)double (Most Common Decimal Type):

• stores decimal numbers with double precision.
• Size: 8 bytes
• Precision: 15–16 decimal digits

double salary = 25000.75;

7)char:

• stores a single character.
• Size: 2 bytes
• Range: 0 to 65,535 (Unicode values)

char grade = 'A';

8)boolean:

• stores true or false values.

boolean isPassed = true;

Non-Primitive (Reference) Data Types:

• These store memory addresses instead of actual values.

1)String:

• Used to store text.
• Immutable (cannot be changed after creation).

String name = "Java";

2)Arrays:

• Used to store multiple values of the same type.
• Fixed size once created.

int[] numbers = {1, 2, 3};
System.out.println(numbers[0]); // 1