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kanaga vimala
kanaga vimala

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## 📘 Learning JavaScript: Functions and Data Types.

JavaScript is a powerful language that forms the backbone of modern web development. One of the first and most important things to understand when learning JavaScript are data types and functions. Here's a quick overview based on what I’ve recently learned.

🔢 JavaScript Data Types

JavaScript has two main types of values: primitive types and objects.

🧩 Primitive Data Types

These are the most basic data types in JavaScript:

  1. String – Text data. 
   let name = "Alice";
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  1. Number – Includes both integers and floats. 
   let age = 25;
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  1. Boolean – True or false values. 
   let isOnline = true;
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  1. Undefined – A variable declared but not assigned a value. 
   let x;
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  1. Null – An explicitly empty value. 
   let y = null;
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  1. Symbol – A unique and immutable value (used rarely, often in advanced cases).

  2. BigInt – For handling large integers beyond the safe integer limit.

🧱 Object Data Types

Objects are more complex and can store collections of data:

  • Objects 
  let person = { name: "John", age: 30 };
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  • Arrays 
  let fruits = ["apple", "banana", "cherry"];
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  • Functions – Yes, functions are objects in JavaScript!

⚙️ JavaScript Functions

Functions are reusable blocks of code that perform a specific task.

🛠 Declaring a Function 

function greet(name) {
  return "Hello, " + name + "!";
}
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🧑‍💻 Calling a Function 

console.log(greet("Alice")); // Output: Hello, Alice!
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➕ Arrow Functions

Introduced in ES6, they offer a shorter syntax:

const add = (a, b) => a + b;
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🧠 Key Takeaways

  • Functions make your code modular and reusable.
  • Understanding data types helps prevent bugs and improves code clarity.
  • JavaScript is loosely typed, so type conversion can happen automatically—be cautious!

✍️ Final Thoughts

Learning JavaScript functions and data types is a great first step into web development. Practice writing different functions and playing around with data types to get more comfortable. Happy coding!

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