Every developer term you will hear — explained in one clear sentence. No jargon.
Application Programming Interface — a set of rules that lets one piece of software talk to another.
A modern JavaScript syntax for handling promises. Makes async code read like sync code.
The total size of all JavaScript your app ships to the browser. Smaller = faster load times.
Content Delivery Network — a network of servers that serve static files from the location nearest to the user.
A function that remembers the variables from where it was defined, even after the outer function has returned.
Cross-Origin Resource Sharing — a browser security mechanism that controls which domains can access your server.
Create, Read, Update, Delete — the four basic operations for any persistent storage system.
Document Object Model — the browser's tree representation of your HTML that JavaScript manipulates.
Don't Repeat Yourself — the principle of reducing code duplication by abstracting repeated logic.
A specific URL your API exposes. Each endpoint handles one type of request (e.g. GET /users).
A static analysis tool that catches syntax errors, enforces code style, and prevents bugs before runtime.
A version control system that tracks changes to your code. The industry standard for collaboration.
JavaScript's behavior of moving variable and function declarations to the top of their scope before execution.
Immediately Invoked Function Expression — a function that runs the moment it's defined.
JavaScript Object Notation — a lightweight text format for storing and transporting data.
JSON Web Token — a compact, self-contained token for securely transmitting information between parties.
A function that runs between the request and the response. Common in Express for logging, auth, etc.
A single repository that contains multiple projects or packages. Popularized by Google and Meta.
A piece of code that adds modern functionality to older browsers that don't natively support it.
An object representing the eventual completion (or failure) of an asynchronous operation.
Representational State Transfer — an architectural style for designing networked APIs using HTTP methods.
Software Development Kit — a collection of tools, libraries, and docs for building on a specific platform.
Server-Side Rendering renders pages on the server. Client-Side Rendering renders them in the browser.
A build step that removes unused exports from your final bundle. Smaller code, faster apps.
An HTTP callback that automatically sends data to another system when an event occurs.