# 📚 Java Programming Language – Part 1/10: Introduction to Java
#Java #Programming #OOP #Beginner #Coding

Welcome to this comprehensive 10-part Java series! Let’s start with the basics.

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## 🔹 What is Java?
Java is a high-level, object-oriented, platform-independent programming language. It’s widely used in:
- Web applications (Spring, Jakarta EE)
- Mobile apps (Android)
- Enterprise software
- Big Data (Hadoop)
- Embedded systems

Key Features:
✔️ Write Once, Run Anywhere (WORA) – Thanks to JVM
✔️ Strongly Typed – Variables must be declared with a type
✔️ Automatic Memory Management (Garbage Collection)
✔️ Multi-threading Support

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## 🔹 Java vs. Other Languages
| Feature | Java | Python | C++ |
|---------------|--------------|--------------|--------------|
| Typing | Static | Dynamic | Static |
| Speed | Fast (JIT) | Slower | Very Fast |
| Memory | Managed (GC) | Managed | Manual |
| Use Case | Enterprise | Scripting | System/Game |

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## 🔹 How Java Works?
1. Write code in .java files
2. Compile into bytecode (.class files) using javac
3. JVM (Java Virtual Machine) executes the bytecode

HelloWorld.java → (Compile) → HelloWorld.class → (Run on JVM) → Output

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## 🔹 Setting Up Java
1️⃣ Install JDK (Java Development Kit)
- Download from [Oracle] :https://www.oracle.com/java/technologies/javase-downloads.html
- Or use OpenJDK (Free alternative)

2️⃣ Verify Installation

java -version
javac -version

3️⃣ Set `JAVA_HOME` (For IDE compatibility)

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## 🔹 Your First Java Program

public class HelloWorld {
    public static void main(String[] args) {
        System.out.println("Hello, World!"); 
    }
}

### 📌 Explanation:
- public class HelloWorld → Class name must match the filename (HelloWorld.java)
- public static void main(String[] args) → Entry point of any Java program
- System.out.println() → Prints output

### ▶️ How to Run?

javac HelloWorld.java  # Compiles to HelloWorld.class
java HelloWorld         # Runs the program

Output:

Hello, World!

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## 🔹 Java Syntax Basics
✅ Case-Sensitive → myVar ≠ MyVar
✅ Class Names → PascalCase (MyClass)
✅ Method/Variable Names → camelCase (myMethod)
✅ Every statement ends with `;`

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## 🔹 Variables & Data Types
Java supports primitive and non-primitive types.

### Primitive Types (Stored in Stack Memory)
| Type | Size | Example |
|-----------|---------|----------------|
| int | 4 bytes | int x = 10; |
| double | 8 bytes | double y = 3.14; |
| boolean | 1 bit | boolean flag = true; |
| char | 2 bytes | char c = 'A'; |

### Non-Primitive (Reference Types, Stored in Heap)
- String → String name = "Ali";
- Arrays → int[] nums = {1, 2, 3};
- Classes & Objects

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### 📌 What’s Next?
In Part 2, we’ll cover:
➡️ Operators & Control Flow (if-else, loops)
➡️ Methods & Functions

Stay tuned! 🚀

#LearnJava #JavaBasics #CodingForBeginners