--- title: 6 use cases of the useEffect ReactJS hook | daily.dev description: The useEffect hook is used to make use of side effects in React. This hook uses an array of "dependencies": variables or states that useEffect listen to for... canonical: https://daily.dev/posts/6-use-cases-of-the-useeffect-reactjs-hook-iphqkuors twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: 6 use cases of the useEffect ReactJS hook | daily.dev og:description: The useEffect hook is used to make use of side effects in React. This hook uses an array of "dependencies": variables or states that useEffect listen to for... og:url: https://daily.dev/posts/6-use-cases-of-the-useeffect-reactjs-hook-iphqkuors og:image: https://api.daily.dev/og/posts/IPhQKUoRS.png og:image:alt: 6 use cases of the useEffect ReactJS hook og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # 6 use cases of the useEffect ReactJS hook **[DEV](https://daily.dev/sources/devto)** · 8 min read · 12 upvotes · 0 comments ## Summary The useEffect hook is used to make use of side effects in React. This hook uses an array of "dependencies": variables or states that useEffect listen to for changes. When their values change, the main body of the useEffect Hook is executed. This behaviour is especially useful for cleaning code that is already running before run it again. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: --- Tags: [#react](https://daily.dev/tags/react) [View this post on daily.dev](https://daily.dev/posts/6-use-cases-of-the-useeffect-reactjs-hook-iphqkuors) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"6 use cases of the useEffect ReactJS hook","url":"https://daily.dev/posts/6-use-cases-of-the-useeffect-reactjs-hook-iphqkuors","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/6-use-cases-of-the-useeffect-reactjs-hook-iphqkuors"},"datePublished":"2021-09-18T23:44:22.476Z","dateModified":"2021-10-07T14:17:10.317Z","description":"The useEffect hook is used to make use of side effects in React. This hook uses an array of \"dependencies\": variables or states that useEffect listen to for...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/9ad1c98d95757cc084c499e37067c545","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/9ad1c98d95757cc084c499e37067c545","isAccessibleForFree":true,"articleSection":"DEV","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"DEV","logo":"https://media.daily.dev/image/upload/t_logo,f_auto/v1/logos/devto","url":"https://daily.dev/sources/devto"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/6-use-cases-of-the-useeffect-reactjs-hook-iphqkuors","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":12},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"react","timeRequired":"PT8M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"DEV","item":"https://daily.dev/sources/devto"},{"@type":"ListItem","position":3,"name":"6 use cases of the useEffect ReactJS hook"}]} ```