📊 Data-Types

Introduction

Data types in Java define the type of data a variable can store. A data type is like a container; it defines what kind of data a variable can hold. Java is a statically-typed language, meaning every variable must have a predefined type.

Why Do We Need Data Types?

Data types ensure memory efficiency and prevent unexpected operations. Without data types, we would not be able to control what kind of data is stored in variables.

Example With Data Types:

int num = 10;
String name = "John";

Using explicit data types improves readability, reliability, and performance.

Real-World Examples:

Student Marks: Using integer type for marks:
```
int marks = 85;
```
Temperature Readings: Using float type for precise values:
```
float temperature = 36.5f;
```

Types of Data Types in Java

Java has two main categories of data types:

Primitive Data Types (Built-in)
Non-Primitive Data Types (User-defined)

1. Primitive Data Types

Primitive data types are the most basic types built into Java. There are 8 types:

Integer Types

Data Type	Size	Default Value	Example Value
`byte`	1 byte	0	`byte b = 127;`
`short`	2 bytes	0	`short s = 32000;`
`int`	4 bytes	0	`int i = 100000;`
`long`	8 bytes	0L	`long l = 10000000000L;`

Floating-Point Types

Data Type	Size	Default Value	Example Value
`float`	4 bytes	0.0f	`float f = 12.34f;`
`double`	8 bytes	0.0d	`double d = 123.456;`

Character & Boolean

Data Type	Size	Default Value	Example Value
`char`	2 bytes	`\u0000`	`char ch = 'A';`
`boolean`	1 bit	`false`	`boolean flag = true;`

2. Non-Primitive Data Types

Non-primitive data types refer to objects and are more complex. The most common are:

String (Text Data)

String name = "Java Programming";

Arrays (Collection of Values)

int[] numbers = {10, 20, 30};

Examples of Using Different Data Types

1. Integer Example

int age = 25;
System.out.println("Age: " + age);

2. Floating-Point Example

double price = 99.99;
System.out.println("Price: " + price);

3. Character Example

char grade = 'A';
System.out.println("Grade: " + grade);

4. Boolean Example

boolean isJavaFun = true;
System.out.println("Is Java Fun? " + isJavaFun);

5. String Example

String message = "Hello, Java!";
System.out.println(message);

Advantages of Using Proper Data Types

Memory Efficiency – Choosing the correct type saves memory.
Performance Optimization – Using smaller types improves execution speed.
Data Integrity – Prevents invalid operations on data.

Conclusion

Java provides a rich set of data types to handle different kinds of information efficiently. Understanding data types is essential for writing robust and optimized Java programs.

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