Coding Foundations glossary
Key terms used throughout the course
Quick definitions for the metrics, structures, and language you will see in lessons, quizzes, readiness exams, and the final exam.
Component
A reusable piece of interface with a clear responsibility.
Props
Inputs that configure a component's output.
State
Values a component owns and updates because of interaction or data.
Hook
A React function that lets components reuse logic across renders.
Server Component
A component that runs on the server and ships no client JavaScript by default.
Client Component
A component marked `use client` that runs in the browser for interactivity.
Optional chaining
The `?.` operator that short-circuits when a property is nullish.
Discriminated union
A union type whose variants share a literal field that narrows the rest.
Promise
A value that represents the eventual result of an asynchronous operation.
REST
An HTTP-based API style centered on resources and standard verbs.
Pull Request
A review package for code changes before merge.
CI
Continuous integration — automated checks (lint, test, build) that run on every change.
Environment variable
Per-deployment config injected via the runtime, never committed to source.
CRUD
Create, Read, Update, Delete — the four basic data operations.
Idempotent
An operation safe to retry without changing the outcome.