JavaScript Academy · Lesson

Naming, Readability, and Common Pitfalls

Naming and readability guidelines; avoid shadowing, magic numbers, and mixed declarations.

Lesson 3 of 38 steps

Naming, Readability, and Common Pitfalls is a free JavaScript Academy lesson on CoddyKit. This is lesson 3 of 3. Any 3 lessons of this learning path are free to read in full — after that, CoddyKit PRO unlocks every lesson, plus hands-on practice with a built-in code editor and a 24/7 AI tutor. It is part of the JavaScript Academy learning path, and your progress syncs across the web and the CoddyKit app. The JavaScript Academy course includes 3 lessons in total.

Intro

Goal: Write readable code. Use clear names, avoid magic numbers, and be careful with shadowing.

Descriptive names
Constants for fixed values
No accidental shadowing

Naming, Readability, and Common Pitfalls — illustration 1

Clear naming demo

Name variables for what they hold, not how they are used. Short but clear wins.

// Use descriptive names
// Avoid single letters or vague words
const itemCount = 3;
const unitPrice = 5;

const totalPrice = itemCount * unitPrice;

console.log("Items:", itemCount);
console.log("Unit price:", unitPrice);
console.log("Total price:", totalPrice);

Naming, Readability, and Common Pitfalls — illustration 2

Naming guidelines

Naming tips:

Nouns for data (userName, totalPrice)
Verbs for functions (computeTotal)
Be consistent with casing (camelCase)

Naming, Readability, and Common Pitfalls — illustration 3

No magic numbers

Promote fixed values to constants (UPPER_CASE is common). It explains intent and eases updates.

// Replace magic numbers with named constants
const TAX_RATE = 0.08;
const SUBTOTAL = 20;

const tax = SUBTOTAL * TAX_RATE;
const finalTotal = SUBTOTAL + tax;

console.log("Tax:", tax);
console.log("Final total:", finalTotal);

Naming, Readability, and Common Pitfalls — illustration 4

Shadowing demo

Shadowing: An inner variable uses the same name and hides the outer one. Prefer unique names when scopes nest.

// Shadowing: inner variable hides an outer one
let score = 10;

function addBonus() {
  // The next line creates a new "score" only inside this function
  let score = 5;
  console.log("Inner score:", score);
}

addBonus();
console.log("Outer score:", score);

Naming, Readability, and Common Pitfalls — illustration 5

Readability checklist

Checklist:

One idea per line
Short functions
Use constants for fixed values
Avoid reused names across scopes

Naming, Readability, and Common Pitfalls — illustration 6

Naming best practice quiz

Quick check: Clear naming.

Naming, Readability, and Common Pitfalls — illustration 7

Answer it in the interactive lesson

Recap

Recap: Use descriptive names, promote fixed values to constants, and avoid shadowing to keep code easy to read and maintain.

Naming, Readability, and Common Pitfalls — illustration 8

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Frequently Asked Questions

Is the “Naming, Readability, and Common Pitfalls” lesson free?

Yes — any 3 lessons of the JavaScript Academy learning path, including “Naming, Readability, and Common Pitfalls”, are free to read in full here on the web. After that, CoddyKit PRO unlocks every lesson, plus interactive practice with a built-in code editor and a 24/7 AI tutor. The JavaScript Academy course includes 3 lessons in total.

What will I learn in “Naming, Readability, and Common Pitfalls”?

Naming and readability guidelines; avoid shadowing, magic numbers, and mixed declarations. You practise JavaScript Academy with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.

Do I need any experience to start JavaScript Academy?

No prior experience is required. JavaScript Academy on CoddyKit is structured for beginners through advanced learners, so you can start here or from the beginning and move at your own pace. This is lesson 3 of 3.

How long does the “Naming, Readability, and Common Pitfalls” lesson take?

Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.

Can I write and run code in this JavaScript Academy lesson?

Yes. Every JavaScript Academy lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.

All lessons in this course

let, const, and avoiding var
Block/Function/Module Scope and the TDZ
Naming, Readability, and Common Pitfalls

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