Table of Contents
10 JavaScript best practices1. Declare and initialize variables at the startWhy is this important?Best practice implementation2. Write modular and reusable functions for better code efficiencyWhy is this important?Best practice implementation3. Eliminate duplicate code for cleaner and more efficient JavaScriptWhy is this important?Best practice implementation4. Use meaningful comments to improve code readabilityWhy is this important?Best practice implementationBest practices for writing comments5. Enable strict mode to catch hidden JavaScript errorsWhy is this important?Best practice implementationHow to use the strict mode6. Optimize DOM manipulations for better performanceWhy is this important?Best practice implementationBest practices for efficient DOM manipulation7. Use recursion wisely to avoid performance issuesWhy is this important?Best practice implementation8. Minimize global variables to prevent conflicts and improve performanceWhy is this important?Best practice implementation9. Use shorthand notation for cleaner and more efficient object literalsWhy is this important?Best practice implementationShorthand notation for arrays10. Use .includes() for efficient existence checks in arraysWhy is this important?Best practice implementationWhen to use .indexOf()Conclusion
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10 JavaScript tips: Best practices to simplify your code

10 JavaScript tips: Best practices to simplify your code

13 mins read
May 30, 2025
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Key takeaways:

  • JavaScript hoists variable declarations, but initializing them early in the process prevents unexpected behavior.

  • Excessive use of global variables can lead to naming conflicts and memory inefficiencies, impacting performance in large applications.

  • Recursion can cause stack overflow errors if not properly managed with base cases.

  • Strict mode ('use strict') prevents silent errors and enforces safer coding practices.

  • Repeated DOM access is inefficient—caching elements improves performance significantly.

Imagine this: you take over a JavaScript project from a teammate. You’re hoping for clean, clear code—but instead, it’s a mess of confusing variables and hard-to-follow logic. Frustrating, right?

Now think about the opposite.

What if your code is the one everyone enjoys working with—simple, clear, and easy to follow?

Writing clean, readable JavaScript makes a big difference. It’s not just a nice-to-have—it can completely change how smoothly things run.

So, how do you take your JavaScript from good to great?

In this blog, we’ll cover 10 simple practices that make your code cleaner, easier to read, and more enjoyable to work with. Ready to level up your JavaScript skills? Let’s get started!

10 JavaScript best practices#

JavaScript powers everything from dynamic websites to complex web applications — but with great flexibility comes great responsibility. No matter where you are in your JavaScript journey, the way you write code can either set you up for long-term success or leave you tangled in technical debt.

Learn JavaScript

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Learn JavaScript

In this course, you’ll learn JavaScript from scratch by building things step by step. You’ll start with simple interactions like displaying messages and buttons that respond to clicks. Then, you’ll teach your code to think using logic, remember things with variables, and make decisions based on the user’s actions. You’ll explore variables, functions, objects, DOM manipulation, event handling, loops, and arrays to build simple yet interactive real-life projects. You’ll go from writing your first line of code to building mini apps like a quiz, a to-do list, and even your digital pet! Every lesson is project-based and beginner-friendly, designed to help you create, not just code. You’ll also practice prompting AI to generate, refine, and debug code, building syntax skills and confidence with AI-enabled workflows. By the end, you’ll confidently understand how to control the page, respond to users, and build interactive web experiences.

10hrs
Beginner
144 Playgrounds
15 Quizzes

These 10 best practices will help you craft code that’s functional, future-proof, and readable.

  1. Declare and initialize variables at the start.

  2. Write modular and reusable functions for better code efficiency.

  3. Eliminate duplicate code for cleaner and more efficient JavaScript.

  4. Use meaningful comments to improve code readability.

  5. Enable strict mode to catch hidden JavaScript errors.

  6. Optimize DOM manipulations for better performance.

  7. Use recursion wisely to avoid performance issues.

  8. Minimize global variables to prevent conflicts and improve performance.

  9. Use shorthand notation for cleaner and more efficient object literals.

  10. Use .includes() for efficient existence checks in arrays.

1. Declare and initialize variables at the start#

Organization is key to writing clean, efficient, and readable code in JavaScript. One of the most fundamental best practices is declaring and initializing variables at the top of your script or function.

Why is this important?#

  • Enhances readability: Developers can quickly locate all variables, making debugging and maintenance easier.

  • Prevents hoisting issues: JavaScript hoists variable declarations, but keeping them at the top eliminates unexpected behavior.

  • Improves maintainability: It’s easier to tweak or modify variable names and values in one place.

  • Reduces undefined errors: Initializing variables when they’re declared prevents accidental usage of undefined values.

Best practice implementation#

Always declare variables at the beginning of a function or script and initialize them immediately to avoid undefined values.

Not recommended: Scattered declarations

Javascript (babel-node)
function calculateTotal(price) {
    let discount;
    let tax = 0.1;
    
    discount = price > 100 ? 10 : 5;  
    let total = price - discount + (price * tax);
    
    return total;
}
// Calling the function
console.log(calculateTotal(120)); // Example usage

This approach makes it harder to track where variables are declared and can cause unnecessary confusion.

Recommended: Clear and organized

Javascript (babel-node)
function calculateTotal(price) {
    let tax = 0.1; 
    let discount = price > 100 ? 10 : 5; 
    let total = price - discount + (price * tax);
    return total;
}
// Calling the function
console.log(calculateTotal(120)); // Example usage

All variables are declared and initialized at the top, making it easy to understand and modify.

Pro tip: Use let and const instead of var:

The var keyword has function scope and can lead to unexpected bugs due to hoisting. Instead, prefer let for reassignable values and const for constants.

// Use let for reassignable variables, const for constants
let x = 5;
const PI = 3.14;

2. Write modular and reusable functions for better code efficiency#

In JavaScript, functions should be concise and focused on a single responsibility. Writing monolithic functions that handle multiple tasks hurts readability and makes maintenance and debugging more difficult.

A better approach is to break down large functions into smaller, modular functions, each designed to perform one specific task. Let’s look at how modular functions improve readability and maintainability.

Why is this important?#

  • Improves readability: A function with a clear, descriptive name that handles one job is easier to understand.

  • Enhances reusability: Smaller functions can be reused across different projects without modification.

  • Simplifies debugging and maintenance: When a function does just one thing, it’s easier to locate and fix errors.

  • Encourages code scalability: Modifying a function that is too broad may cause unintended side effects. Keeping functions specialized prevents this issue.

Best practice implementation#

Not recommended: One function doing too much

function table(columns, rows, item) {
    // Creates a table and searches it for the passed item
}
A function doing too much

This function tries to create a table and search within it, violating the single responsibility principle (SRP).

Recommended: Modular and readable

function createTable(columns, rows) {
    // Creates a table with the specified columns and rows
}
function searchTable(table, item) {
    // Searches the table for the specified item
}
A function doing a single task

Each function does one thing and is named accordingly, making the code easier to read, debug, and maintain.

Pro tip: Use descriptive function names

A function’s name should clearly describe its purpose without requiring users to read through the code. If you have to explain what a function does, it probably needs refactoring.

function fetchUserData(userId) {
    // Retrieves user data from the database
}

function formatCurrency(amount) {
    // Converts a number to a currency format
}

If you’re struggling with JavaScript, explore Educative’s interactive course to improve your skills with hands-on learning!

Cover
Learn JavaScript

In this course, you’ll learn JavaScript from scratch by building things step by step. You’ll start with simple interactions like displaying messages and buttons that respond to clicks. Then, you’ll teach your code to think using logic, remember things with variables, and make decisions based on the user’s actions. You’ll explore variables, functions, objects, DOM manipulation, event handling, loops, and arrays to build simple yet interactive real-life projects. You’ll go from writing your first line of code to building mini apps like a quiz, a to-do list, and even your digital pet! Every lesson is project-based and beginner-friendly, designed to help you create, not just code. You’ll also practice prompting AI to generate, refine, and debug code, building syntax skills and confidence with AI-enabled workflows. By the end, you’ll confidently understand how to control the page, respond to users, and build interactive web experiences.

10hrs
Beginner
144 Playgrounds
15 Quizzes

3. Eliminate duplicate code for cleaner and more efficient JavaScript#

Duplicate code is one of the biggest culprits behind messy, inefficient, and hard-to-maintain JavaScript. Repeating the same logic multiple times clutters your code, makes debugging difficult, and increases the likelihood of errors.

The solution? Identify repetitive patterns and extract them into reusable functions.

Why is this important?#

  • Reduces visual clutter: Keeps your code clean and organized.

  • Improves maintainability: Changes must only be made in one place instead of multiple locations.

  • Enhances debugging: Fixing bugs becomes easier since a single function controls all instances of an operation.

  • Boosts reusability: Encapsulating logic into functions allows reuse throughout the project.

Best practice implementation#

Not recommended: Duplicate code

Javascript (babel-node)
var x = 5;
var y = 6;
x = x * 2;
y = y * 2;
console.log("x:", x, "y:", y);

This code repeats the same multiplication logic twice for different variables, making it inefficient.

Recommended: Eliminate duplication with a function

Javascript (babel-node)
var x = 5;
var y = 6;
function double(value) {
    return value * 2;
}
x = double(x);
y = double(y);
console.log("x:", x, "y:", y);

Refactoring duplicate code into a function makes the code cleaner, reusable, and easier to maintain.

Pro tip: Use higher-order functions for more efficiency

If you have multiple values to process, consider using array methods like map(), which eliminates redundancy further:

let numbers = [5, 6];

let doubledNumbers = numbers.map(num => num * 2);

console.log(doubledNumbers); // Output: [10, 12]

This approach scales better when dealing with multiple variables

4. Use meaningful comments to improve code readability#

Code should be self-explanatory, but even the clearest code can benefit from well-placed comments. Thoughtful comments help developers understand your logic, catch potential mistakes, and improve collaboration.

Many teams follow the “leave one comment per function” rule to ensure clarity without clutter. If you’re ever unsure whether to add a comment, just do it! Unnecessary comments can be removed later, but missing comments can slow down debugging and maintenance.

Why is this important?#

  • Improves readability: Helps others (and future you) understand the purpose of code at a glance.

  • Aids debugging: Clarifies intended functionality, making it easier to spot logic errors.

  • Enhances collaboration: Team members can quickly understand and modify the code.

  • Acts as documentation: Provides context when returning to code after weeks or months.

Best practice implementation#

Not recommended: No comments

var x = 5;

If a new developer joins the project, they might not know what x represents.

Recommended: Meaningful comment

// Declares and initializes a variable x with the value 5
var x = 5;

Even a simple comment can prevent confusion!

Best practices for writing comments#

  • Comment on every function. Briefly explain what it does.

Javascript (babel-node)
// Calculates the area of a rectangle given width and height
function calculateArea(width, height) {
    return width * height;
}
let area = calculateArea(5, 10);
console.log("Area:", area);

  • Explain complex logic. If a code block is tricky, summarize its purpose.

Javascript (babel-node)
// Convert Celsius to Fahrenheit using the formula: (C × 9/5) + 32
function convertToFahrenheit(celsius) {
    return (celsius * 9/5) + 32;
}
let tempF = convertToFahrenheit(25);
console.log("Temperature in Fahrenheit:", tempF);

  • Use block comments for multistep explanations.

Javascript (babel-node)
/*
   This function takes an array of numbers and returns the sum
   It iterates over each number, adding it to the total sum
*/
function sumArray(numbers) {
    let sum = 0;
    for (let num of numbers) {
        sum += num;
    }
    return sum;
}
let numbers = [1, 2, 3, 4, 5];
console.log("Sum of array:", sumArray(numbers));

  • Avoid obvious or redundant comments. Try to avoid using unnecessary comments in the code. 

// Add 1 to i
i = i + 1;

The code is already clear—no need to explain basic operations.

Pro tip: Use TODO comments for future enhancements

// TODO: Optimize this function to handle larger datasets efficiently

Helps track pending improvements!

5. Enable strict mode to catch hidden JavaScript errors#

JavaScript is a forgiving language, often letting silent errors slip through without throwing explicit warnings. While this flexibility helps get code to run, it can lead to unexpected behavior, hidden bugs, and security risks.

The solution? Enable strict mode ('use strict';). This mode enforces stricter parsing and error handling, helping you catch mistakes early before they cause bigger problems.

Why is this important?#

  • Catches silent errors: JavaScript may ignore or resolve certain mistakes ambiguously without strict mode.

  • Prevents undeclared variables: Assigning values to undeclared variables throws an error instead of creating global variables accidentally.

  • Disallows dangerous syntax: Stops unsafe operations, like duplicate parameter names or writing to read-only properties.

  • Improves performance: Strict mode enforces better coding practices, reducing the risk of silent errors and unintended global variables.

Best practice implementation#

Not recommended: Without strict mode, silent errors may occur

Javascript (babel-node)
x = 10;  // JavaScript allows this, even though 'x' was never declared!
console.log(x); // Output: 10 (but this is a bad practice)

This mistake could lead to unexpected global variable creation without any warnings.

Recommended: Using strict mode for safer code

Javascript (babel-node)
'use strict';
x = 10;  // Throws ReferenceError: x is not defined
console.log(x);

Now, JavaScript forces you to explicitly declare variables, preventing accidental global variable creation.

How to use the strict mode#

  • Apply strict mode to the entire script. It is best for full-scale projects. 

'use strict';
function calculateTotal(price, tax) {
    return price + tax;
}
Apply strict mode to the entire script

  • Apply strict mode to specific functions. It is best for selective enforcement.

function calculateTotal(price, tax) {
    'use strict';
    return price + tax;
}
Apply strict mode to specific functions

  • Strict mode in browser consoles. 

// Enabling strict mode temporarily in a browser console
'use strict';

Note: Strict mode must be declared before any executable statements in a script or function.

Pro tip: Strict mode also prevents common errors

Prevents accidental global variables:

'use strict';
myVar = 5; // Uncaught ReferenceError: myVar is not defined

Disallows duplicate function parameters:

'use strict';
function sum(a, a) {  // SyntaxError: Duplicate parameter name not allowed
    return a + a;
}

Restricts eval() and argument usage:

'use strict';
eval("var x = 2;");
console.log(x); // ReferenceError: x is not defined

6. Optimize DOM manipulations for better performance#

The Document Object Model (DOM) is a fundamental part of web development, allowing JavaScript to dynamically interact with and update HTML elements. However, repeatedly accessing the DOM can cause:

  • Performance slowdowns due to frequent rerenders

  • Visual clutter in the code

  • Unnecessary processing overhead

A better approach is to cache your DOM elements in variables and access them only once, reducing redundant lookups and improving efficiency.

Why is this important?#

  • Boosts performance: Reduces unnecessary DOM traversals, making scripts run faster.

  • Enhances readability: Code looks cleaner and more structured.

  • Simplifies maintenance: DOM references are stored in variables, making updates easier.

  • Minimizes repetitive queries: Instead of searching the DOM multiple times, you retrieve elements from a variable.

Best practice implementation#

Not recommended: Repeated DOM access

function accountInfo() {
    var email = $("#accounts").find(".email").val();
    var accountNumber = $("#accounts").find(".accountNumber").val();
}
Repeated DOM access

The $("#accounts") selector is used twice, making the function inefficient.

Recommended: Optimized with cached DOM reference

function accountInfo() {
    var $accounts = $("#accounts"); // Caching the DOM reference
    var email = $accounts.find(".email").val();
    var accountNumber = $accounts.find(".accountNumber").val();
}
Optimized with cached DOM reference

Now, the DOM is accessed only once, improving efficiency and readability.

Best practices for efficient DOM manipulation#

  • Cache DOM elements in variables. 

var $button = $("#submitButton"); // Store reference  
$button.text("Processing..."); // Use variable instead of re-querying DOM

  • Batch DOM updates instead of accessing elements multiple times.

Inefficient:

$("#content").text("New Content");
$("#content").css("color", "blue");
$("#content").fadeIn();

Optimized:

$("#content").text("New Content").css("color", "blue").fadeIn();

Chaining jQuery methods reduces redundant lookups.

  • Use document fragments for bulk insertions.

var fragment = document.createDocumentFragment();
for (let i = 0; i < 10; i++) {
    let div = document.createElement("div");
    div.textContent = "Item " + i;
    fragment.appendChild(div);
}
document.getElementById("container").appendChild(fragment);
Efficient bulk insertion using document fragments

This prevents multiple reflows compared to appending elements one by one.

Pro tip: Use $ prefix for jQuery variables

A common convention in jQuery-based projects is to prefix cached DOM elements with $, making them easily recognizable.

var $header = $("#header"); // Clearer indication of a jQuery object

This small convention improves code readability and maintainability.

If you want to discover more JavaScript tips and learn how to simplify your coding, check out Educative’s interactive course!

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Simplifying JavaScript: A Handy Guide for Software Engineers

In this course, you’ll learn to write modern JavaScript from the ground up. But instead of going over every possible edge case, you’ll focus on the syntax that has a significant impact in your day-to-day work. As you review each construct, you’ll learn not just how to use it, but, more importantly, when to. Your time is valuable, and this course, based on the Pragmatic Programmers’ book, Simplifying JavaScript, covers all the most important language features. And with 51 tips in total, you'll be able to jump into and out of this course easily. Before you know it, you'll be a productive and modern JavaScript developer.

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Beginner
282 Playgrounds
27 Quizzes

7. Use recursion wisely to avoid performance issues#

Recursion is powerful, but excessive nesting can hurt readability and performance. Deeply nested recursive functions are difficult to follow, debug, and maintain.

Why is this important?#

  • Improves readability: Minimizes complex nesting that’s hard to trace.

  • Enhances debugging: Shallow functions are easier to troubleshoot.

  • Prevents stack overflow errors: Overuse of recursion can cause excessive memory consumption.

  • Optimizes performance: In many cases, iteration is a better alternative.

Best practice implementation#

Not recommended: Too many nested recursive calls

function function1(a, b) {
    function function2() {
        function function3() {
            // Too complex and hard to follow!
        }
        function3();
    }
    function2();
}
Too many nested recursive calls

This deep nesting makes the logic harder to track.

Recommended: Refactored for clarity

function function3() {
    // Base case logic
}
function function2() {
    function3(); // Call function directly
}
function function1(a, b) {
    function2();
}
Refactored code for better readability and maintainability

Each function remains clear and modular, improving readability.

Pro tip: Consider iteration over recursion

If recursion isn’t necessary, convert it into a loop to avoid excessive function calls.

function factorial(n) {
    let result = 1;
    for (let i = 2; i <= n; i++) {
        result *= i;
    }
    return result;
}

This is more memory-efficient than recursive factorial implementations.

8. Minimize global variables to prevent conflicts and improve performance#

In JavaScript, variable scope determines where a variable can be accessed. Global variables—which exist outside of functions—should be avoided because they:

  • Increase the risk of accidental overwrites.

  • Cause naming conflicts in large applications.

  • Consume memory unnecessarily since they persist until the page is closed.

Instead, use local variables within functions or block scopes to keep your code modular, efficient, and error-free.

Why is this important?#

  • Prevents conflicts: Global variables can unintentionally overwrite built-in JavaScript objects.

  • Improves performance: Global variables persist in memory, while local variables are released after use.

  • Enhances maintainability: Keeping variables local makes debugging easier and reduces side effects.

  • Encourages modular code: Using function or block-scoped variables keeps code structured and scalable.

Best practice implementation#

Not recommended: Global variable pollution

Javascript (babel-node)
var myVar = "I am global"; // Accessible everywhere
function localVariable() {
    var myVar = "I am local"; // Shadowing the global variable
    console.log(myVar); // "I am local"
}
console.log(myVar); // "I am global"
localVariable();

This approach can lead to unintended overwrites and conflicts.

Recommended: Scoped variables

Javascript (babel-node)
function localVariable() {
    let myVar = "I am local"; // Block-scoped, no conflict
    console.log(myVar); // "I am local"
}
localVariable();
console.log(typeof myVar); // undefined (safe, no global pollution)

Using let or const ensures variables remain local, preventing accidental overwrites.

Pro tip: Use IIFE (Immediately invoked function expressions) to maintain local scope

If you must use variables globally, encapsulate them in an IIFE to prevent conflicts.

(function () {
    let myVar = "I am safely scoped"; // Encapsulated within function
    console.log(myVar);
})();

This keeps variables isolated from the global scope.

9. Use shorthand notation for cleaner and more efficient object literals#

Shorthand notation improves readability, efficiency, and maintainability when defining objects or arrays in JavaScript. Instead of setting properties or array elements line by line, declare them directly within an object or array literal.

This reduces clutter, makes code easier to scan, and minimizes redundancy, especially as objects and arrays become more complex.

Why is this important?#

  • Saves line space: Objects and arrays are more compact and visually cleaner.

  • Enhances readability: Team members can quickly understand object structures.

  • Improves maintainability: Easier to modify and update object properties.

  • Reduces boilerplate code: Eliminates repetitive assignments and increases efficiency.

Best practice implementation#

Not recommended: Longhand object creation

var computer = new Object();
computer.caseColor = "black";
computer.brand = "Dell";
computer.value = 1200;
computer.onSale = true;
Longhand object creation

This approach requires multiple lines, making the code longer and harder to read.

Recommended: Shorthand object notation

var computer = {
    caseColor: "black",
    brand: "Dell",
    value: 1200,
    onSale: true
};
Shorthand object notation

Properties are neatly declared inside the object, making the code cleaner.

Shorthand notation for arrays#

Longhand array declaration

var computerBrands = new Array();
computerBrands[0] = "Dell";
computerBrands[1] = "Apple";
computerBrands[2] = "Lenovo";
computerBrands[3] = "HP";
computerBrands[4] = "Toshiba";
computerBrands[5] = "Sony";
Longhand array declaration

Manually setting array elements is inefficient.

Shorthand array declaration

var computerBrands = ["Dell", "Apple", "Lenovo", "HP", "Toshiba", "Sony"];
Shorthand array declaration

This approach is more concise, readable, and efficient.

Pro tip: Use shorthand property names for objects

If the variable name and object property name are the same, you can use ES6 shorthand property names:

let brand = "Dell";
let price = 1200;

// Shorthand property assignment
let computer = { brand, price };

console.log(computer); // { brand: "Dell", price: 1200 }

Saves even more space by omitting redundant key-value pairs.

10. Use .includes() for efficient existence checks in arrays#

Checking whether a value exists in an array is a common operation in JavaScript. Instead of loops or manual searches, the .includes() method provides a cleaner, faster, and more readable solution by returning a boolean (true or false).

Why is this important?#

  • Simplifies code: Avoids complex loops and conditional checks.

  • Enhances readability: Clearly expresses the intent of checking for existence.

  • Improves performance: Optimized for quick lookups, especially for small arrays.

  • Works with both strings and arrays: A Versatile method for various use cases.

Best practice implementation#

Not recommended: Using indexOf() for existence check

Javascript (babel-node)
const sections = ["contact", "shipping"];
function displayShipping(sections) {
    return sections.indexOf("shipping") !== -1; 
}
console.log(displayShipping(sections)); // true

While indexOf() works, checking for -1 makes the code harder to read.

Recommended: Using .includes() for clarity

Javascript (babel-node)
const sections = ["contact", "shipping"];
function displayShipping(sections) {
    return sections.includes("shipping"); // Returns true if found
}
console.log(displayShipping(sections)); // true

The .includes() function clearly expresses intent and improves readability.

When to use .indexOf()#

If you need to find the index of a value (not just check its existence), use .indexOf():

Javascript (babel-node)
const sections = ["contact", "shipping"];
let index = sections.indexOf("shipping"); 
if (index !== -1) {
    console.log(`'shipping' found at index ${index}`);
}

Use .indexOf() when you need the position of an item, not just a boolean check.

Pro tip: Use .some() for more complex conditions

If checking custom conditions, Array.some() is a great alternative:

const users = [
    { name: "Alice", role: "admin" },
    { name: "Bob", role: "user" }
];

const isAdminPresent = users.some(user => user.role === "admin");

console.log(isAdminPresent); // true

The .some() method checks object properties inside an array.

Conclusion#

Mastering JavaScript goes beyond making code work—it’s about writing clean, efficient, and maintainable code that others can easily read and understand. Following these best practices will improve your coding skills, enhance collaboration, reduce debugging time, and boost overall performance.

Each technique contributes to a more structured and scalable JavaScript codebase, from declaring variables initially and eliminating duplicate code to optimizing DOM manipulations and using shorthand notations.

Ready to take your JavaScript skills to the next level? Start implementing these best practices today and see the difference!

To explore more JavaScript tips and hands-on learning, check out Educative’s interactive course and sharpen your skills with real-world coding challenges!

Frequently Asked Questions

How do you simplify JavaScript code?

Simplify JavaScript by writing modular functions, reducing redundancy, and leveraging ES6+ features like destructuring, arrow functions, and template literals. Use shorthand syntax, cache DOM elements, and enable strict mode ('use strict') to catch errors and enhance reliability.

What are the three basic rules for JavaScript?

The three key rules of JavaScript are as follows:

  • Declare variables before use to avoid global scope issues.
  • JavaScript is case-sensitive (e.g., myVariable ≠ myvariable).
  • Lexical scoping: Inner functions can access outer variables, but not vice versa.

How can I make JavaScript better?

Minimize global variables, optimize loops, and handle errors with try...catch. Write readable, well-commented code and avoid deep nesting. Use array methods like map() and filter() for cleaner scripts. Stay updated with ES6+ for optimized, future-proof code.

What is the best practice for declaring a variable in JavaScript?

The best practice is to use let and const instead of var. The const function should be used for values that don’t change, ensuring immutability, while let is ideal for variables that need reassignment. Avoid declaring variables globally to prevent conflicts and memory leaks. Always initialize variables when declaring them to avoid undefined errors and improve code clarity.

Written By:
Ryan Thelin
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