Let’s break down the difference between an array and an object in JavaScript (and generally in programming):
🔹 Array
- Definition: An ordered collection of values (indexed by numbers).
- Key: Uses numeric indexes (0, 1, 2, …).
- Use case: Best when you need to store a list of items in order.
- Methods: Has many built-in methods like
.push(),.pop(),.map(),.filter(),.forEach(). - Example:
let fruits = ["apple", "banana", "mango"]; console.log(fruits[0]); // "apple"
🔹 Object
- Definition: A collection of properties in key–value pairs.
- Key: Uses string (or symbol) keys, not numbers by default.
- Use case: Best when you want to store data with labels or properties.
- Methods: Doesn’t have array methods, but you can use
Object.keys(),Object.values(),Object.entries(). - Example:
let person = { name: "John", age: 30, city: "Delhi" }; console.log(person.name); // "John" console.log(person["age"]); // 30
🔑 Main Differences
| Feature | Array | Object |
|---|---|---|
| Data Structure | Ordered list | Key–value pairs |
| Indexing | Numeric (0,1,2,…) | String (or Symbol) keys |
| Use Case | Store multiple values in order | Store related data with labels |
| Built-in Methods | Many (push, pop, map, filter) | Fewer (Object.keys, values) |
| Iteration | Loops, forEach, map | for...in, Object.keys() |
✅ Rule of Thumb:
- Use an array when the order of elements matters.
- Use an object when you need to describe an entity with named properties.