ReasonJun

Web Vitals are a set of metrics that measure the user experience of a web page. They are designed to help developers understand how their pages are performing and identify areas where they can improve. The three core Web Vitals are: Largest Contentful Paint (LCP): This measures the time it takes for the largest contentful paint (LCP) element on a page to render. The LCP element is typically the ..

useCallback is a hook in React that is used to memoize and optimize the creation of a function, especially when passing that function down to child components. It is primarily used to avoid unnecessary re-creation of function references, which can lead to unnecessary re-renders of child components. When a component renders, any functions defined within the component body are recreated each time ..

App.js code : import { useEffect, useState } from 'react'; import './App.css'; import B from './components/B'; import A from './components/A'; function App() { const [value, setValue] = useState(''); const [posts, setPosts] = useState([]); useEffect(() => { fetch('https://jsonplaceholder.typicode.com/posts') .then((res) => res.json()) .then((posts) => setPosts(posts)); }, []); return ( setValue(..