JavaScript Core Concepts
Master the fundamentals of JavaScript with this comprehensive flashcard deck designed for beginners and aspiring developers. This collection covers essential JavaScript core concepts including variables, data types, functions, scope, closures, the DOM, events, and asynchronous programming. Whether you're preparing for coding interviews, improving your front-end development skills, or starting your programming journey, these flashcards provide a quick and effective way to reinforce key concepts. Each card is structured to help you understand not just definitions, but practical usage in real-world scenarios. This deck is ideal for students, self-taught developers, and professionals looking to strengthen their JavaScript foundation. Study anytime, revise faster, and build confidence in your coding skills with this easy-to-follow learning resource.
Cards in this deck
What is JavaScript?
JavaScript is a high-level, interpreted programming language used to create dynamic and interactive content on websites.
What are the different data types in JavaScript?
Primitive types include string, number, boolean, null, undefined, bigint, and symbol. Non-primitive type is object.
What is the difference between let, const, and var?
var is function-scoped let is block-scoped const is block-scoped and cannot be reassigned
What is a closure in JavaScript?
A closure is a function that remembers variables from its outer scope even after the outer function has finished executing.
What is the DOM?
The Document Object Model (DOM) is a programming interface that allows JavaScript to interact with HTML elements.
What is an event in JavaScript?
An event is an action or occurrence (like a click or keypress) that JavaScript can respond to.
What is the difference between == and ===?
== compares values with type conversion === compares both value and type (strict equality)
What is a function in JavaScript?
A function is a reusable block of code designed to perform a specific task.
What is an arrow function?
A shorter syntax for writing functions using =>, and it does not have its own this context.
What is 'this' keyword?
It refers to the object that is executing the current function.
What is an array?
An array is a data structure used to store multiple values in a single variable.
What is an object in JavaScript?
An object is a collection of key-value pairs used to store structured data.
What is JSON?
JSON (JavaScript Object Notation) is a format used to store and exchange data.
What is asynchronous programming?
It allows code to run without blocking execution, using callbacks, promises, or async/await.
What is a Promise?
A Promise represents a value that may be available now, later, or never.
What is async/await?
A modern way to handle asynchronous operations, making code look synchronous.
What is hoisting?
JavaScript moves variable and function declarations to the top of their scope during execution.
What is scope?
Scope determines where variables can be accessed in the code.
What is event bubbling?
Events propagate from the target element up to parent elements.
What is localStorage?
A browser storage that allows saving data persistently in key-value format.