Chapter VIII · Arrays
Array Indexes
Array indexes represent the numerical position of items in an array, starting at zero.
01 How It Works
Think of sequential apartment door numbers lining a hallway corridor.
Items are addressed via bracket notation containing their exact zero-based integer index.
example.js
const colors = ["red", "green", "blue"];
console.log(colors[0]); // "red"
console.log(colors[2]); // "blue"
1. Target an array reference variable.
2. Provide target integer index inside brackets [i].
3. Retrieve or reassign the item.
02 Practical Example
Here is how you might see this concept applied in real-world code:
practical.js
const items = ["a", "b", "c"];
items[1] = "z"; // Reassign index 1
Key Takeaway
JavaScript arrays are zero-indexed, meaning the first item sits at index 0.