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Why do React components need to start with capital letters?

Bhat Aasim on September 21, 2024

Why do React components need to start with capital letters? If you’ve ever worked with React, you might have noticed that component names always...

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Alexander • Sep 22

What about const SomeName = "some value" and projects without Babel?

Bhat Aasim • Sep 22

SomeName simply a variable, not a react component. Capitalization rule will not apply here, because its not being used as a react component here.

Projects without babel, then React.createElement() Api is used Explicitly.

BTW, using Capital letters in Components, helps react to differentiate between Native Elements and custom Components.

Eg.

React.createElement('div'); 
// Interpreted as a native HTML <div> element

React.createElement(MyComponent); 
// Interpreted as a custom React component

If MyComponent is written in lower case (myComponent), React will look for a native HTML element <myComponent> which doesn't exists, causing the app to fail.

Alexander • Sep 22

I see the point with createElement, but I still can write lower case functional component on a project without Babel and still get the error. So it's not Babel concern, as your article states