📦 Data Types: Think Containers

Data types define what kind of value a variable can hold. Think of them as different types of containers - each designed for specific contents.

Common Data Types

🔢 Numbers

• Integers: Whole numbers (1, 42, -7)
• Floats: Decimal numbers (3.14, -0.5, 99.99)

Use for: age, price, quantity, scores

📝 Strings (Text)

Any text enclosed in quotes: "Hello", "john@email.com", "123 Main St"

Use for: names, addresses, messages, emails

✅ Booleans (True/False)

Only two values: true or false

Use for: isLoggedIn, hasPermission, isActive

📋 Arrays (Lists)

Ordered collection: [1, 2, 3] or ["apple", "banana", "orange"]

Use for: shopping cart, todo list, user list

📁 Objects

Key-value pairs: {name: "Alice", age: 25}

Use for: user profiles, product details, settings

❓ Null/Undefined

Represents "nothing" or "not set yet"

Use for: optional fields, missing data

Why Data Types Matter

Type Conversion

Sometimes you need to change types:

• String to Number: "42" → 42
• Number to String: 42 → "42"
• String to Boolean: "true" → true

Real-World Examples

• 🛒 Shopping Cart: quantity (number), productName (string), inStock (boolean)
• 👤 User Profile: age (number), username (string), isVerified (boolean)
• 📧 Email: subject (string), timestamp (number), isRead (boolean)

Choosing the Right Type

• 💰 Money: Use numbers (19.99, not "19.99")
• 📞 Phone Numbers: Use strings ("555-1234") - you don't do math with them!
• ✅ Yes/No Questions: Use booleans (true/false)
• 📋 Multiple Items: Use arrays

The bottom line: Data types are like choosing the right container for the job. Use numbers for math, strings for text, booleans for yes/no, and arrays for lists. Pick the right type, and your code will work smoothly!