🎯 What You'll Learn
- ✓ What is JavaScript?
- ✓ Who created JavaScript and in what year?
- ✓ What is ECMAScript?
- ✓ How do you include JavaScript in an HTML file?
- ✓ What does console.log() do?
Sharpen your Javascript Fundamentals skills with targeted coding flashcards.
JavaScript is a high-level, interpreted programming language primarily used for web development to make web pages interactive. It is the scripting language of the Web, supported by all modern browsers, and follows the ECMAScript specification.
JavaScript was created by Brendan Eich in 1995 while working at Netscape. It was initially called Mocha, then LiveScript, before being renamed JavaScript.
ECMAScript (ES) is the standardized scripting language specification upon which JavaScript is based. The latest stable version is ES2023, with JavaScript implementing all ES features plus browser-specific ones.
Use the <script> tag in the HTML, either inline with code between tags or externally via <script src="script.js"></script>. Place it before the closing </body> tag for better performance.
console.log() outputs a message to the browser's console for debugging and logging. It can log multiple arguments of any type, like console.log('Hello', 42);.
Variables can be declared using var (function-scoped), let (block-scoped), or const (block-scoped constant). let and const were introduced in ES6.
The primitive types are string, number, bigint, boolean, undefined, null, and symbol. They are immutable basic values.
Use the typeof operator, e.g., typeof 'hello' returns 'string'. It returns a string describing the type.
null represents an intentional absence of value, while undefined means a variable has been declared but not assigned. typeof null is 'object', a historical bug.
Type coercion is JavaScript's automatic conversion of values between types, like '5' + 1 becoming '51'. Use === for strict equality to avoid it.
Arithmetic operators include + (addition), - (subtraction), * (multiplication), / (division), % (modulus), ** (exponentiation). They work on numbers.
Comparison operators like ==, ===, !=, !==, >, etc., return a boolean (true or false). === checks value and type.
Flashcards
Flip to reveal
Focus Mode
Spaced repetition
Multiple Choice
Test your knowledge
Type Answer
Active recall
Learn Mode
Multi-round mastery
Match Game
Memory challenge
Programming is one of the most valuable and versatile skills in the modern economy. Whether you're a bootcamp graduate solidifying fundamentals, a CS student preparing for exams, or a developer prepping for FAANG interviews, these flashcards help you master the concepts that separate junior developers from senior engineers — algorithms, system design, and software architecture.
After reviewing an algorithm or data structure card, implement it from scratch in your preferred language to build muscle memory.
For every algorithm, know its Big O time and space complexity — this is the most commonly tested concept in technical interviews.
Focus on recognizing problem patterns (sliding window, two pointers, dynamic programming) rather than memorizing individual solutions.
Yes, our programming decks cover algorithms, data structures, and system design concepts frequently tested in technical interviews at top companies.
Our flashcards focus on language-agnostic concepts, but examples reference popular languages like Python, JavaScript, Java, and C++.
We offer decks from introductory programming concepts to advanced topics like distributed systems and compiler design.
Our flashcards cover concepts in Python, JavaScript, Java, C++, Go, and more, with language-agnostic cards on algorithms and design patterns.
Yes, we have extensive coverage of arrays, linked lists, trees, graphs, sorting algorithms, dynamic programming, and complexity analysis.
Absolutely — our decks focus on the algorithmic patterns, system design concepts, and problem-solving frameworks tested at top tech companies.