Glossary
Please note that the glossary is currently under construction and some sections may be incomplete or subject to changes.
Children
When you nest content inside a JSX tag, the parent component will receive that content in a prop called children.
Class Component
A class component is a component defined as a JavaScript class (opens in a new tab).
Clone Element
The cloneElement is a React API that lets you create a new React element using another element as a starting point.
Component
A component is a piece of the UI (user interface) that has its own logic and appearance. A component can be as small as a button, or as large as an entire page.
Conditional Rendering
Conditional Rendering is the process of displaying different UI based on certain conditions.
Context
An alternative to passing props.
Context lets a parent component provide data to the entire tree below it. There are many uses for context.
Context Consumer
The component that consumes the context value.
As for Context.Consumer component, It's an older way to read context, Before useContext existed.
Context Provider
A component to provide that context from the component that specifies the data.
Context Value
The data that is provided by the context provider.
Create Ref
A Legacy React API that creates a ref object which can contain arbitrary value.
Deps
The deps is an abbreviation for React Hook's dependencies array.
Display Name
The displayName is a string used in debugging messages. It is used by React DevTools to determine what to display for the name of a component or context.
Element
A plain object describing a component instance or DOM node and its desired properties.
Elements are the smallest building blocks of React apps.
Event Handler
A function that will be triggered in response to interactions like clicking, hovering, focusing form inputs, and so on.
ExR
An abbreviation for "ESLint x React".
Also used as the namespace for ESLint x React's types.
FlatConfig
ESLint's new config system (opens in a new tab).
It's usually a eslint.config.js file under the root directory of your project.
Forward Ref
A React API that lets your component expose a DOM node to parent component with a ref (opens in a new tab).
Fragment
A React Component that lets you group elements without a wrapper node.
Fragment Syntax
The shorthand syntax for a Fragment in JSX. It looks like <>...</>.
Function Component
A function component is a component defined as a JavaScript function (opens in a new tab).
Key
The key prop is a string or a number that uniquely identifies it among other items in that array.
List Rendering
The process of rendering components from a collection of data.
Memo
The memo is a React API lets you skip re-rendering a component when its props are unchanged.
Props
When React sees an element representing a user-defined component, it passes JSX attributes and children to this component as a single object. We call this object "props".
Ref
The ref lets you referencing values in React.
Legacy React APIs
APIs are exported from the react package, but they are not recommended for use in newly written code. See the linked individual API pages for the suggested alternatives.
Legacy Children
The Children Object with a series of Legacy React APIs that lets you manipulate and transform the JSX you received as the children prop (opens in a new tab).
Legacy Component
The Component base class for the React components defined as JavaScript classes (opens in a new tab).
LegacyConfig
ESLint's current config system (opens in a new tab).
It's usually a .eslintrc.* file under the root directory of your project.
FAQ
Q: Can you define some other term that I find confusing in ESLint x React?
A: Sure, send it on and I'll add it to the glossary!
Q: Wikipedia doesn't agree with your definitions.
A: Yeah, It's time to improve Wikipedia.
Q: I don't agree with your definitions.
A: Ok.
Q: Change your definitions to what I want!
A: Nope. This glossary uses react.dev (opens in a new tab), reactjs.org (opens in a new tab) and MDN (opens in a new tab) as the trusted sources. But You can help improve it if you find sections that don't match the sources specified.
Legal Notice
This glossary is not officially endorsed by ESLint (opens in a new tab), React (opens in a new tab) or Meta (opens in a new tab).
For new terms created by ESLint x React, the final interpretation belongs to the authors of ESLint x React.