Frontend engineering · Frameworks

Props

Also called: Properties, Component props, Component inputs

Data a parent component passes to a child component, like passing arguments to a function. The child reads it but doesn't change it, and uses it to decide what to show.

In detail

Think of a component as a coffee machine and props as the buttons you press: large or medium, sugar or no sugar. Same machine, different options, different coffee. For example, in <Button type="primary" text="Submit" />, type and text are props.

Props flow one way: from parent to child. A child component shouldn't change the props it receives directly. If it needs something changed, the parent passes down a callback function (like onChange), and the child calls it to tell the parent to make the change.

How it differs from State: props come from outside, state is what the component keeps track of itself. When a piece of data has to be passed down through many layers of components, that's called "prop drilling," and you might switch to global state or Context instead.

Developer infoTerm ID, DOM cues, match priority

Term ID: eng-props
DOM selectors: No DOM cues. This concept isn't detected directly on a page.
Priority: 1 · when several match at the same level, the higher priority wins
Version: v1 · updated Sep 29, 2026