--- title: Data structures in JavaScript: Dictionaries | daily.dev description: ES6 introduced the Map data structure, providing us a proper tool to handle this kind of data organization. What is a Map? It's a data structure that allows to... canonical: https://daily.dev/posts/data-structures-in-javascript-dictionaries-pkcjokkyu twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Data structures in JavaScript: Dictionaries | daily.dev og:description: ES6 introduced the Map data structure, providing us a proper tool to handle this kind of data organization. What is a Map? It's a data structure that allows to... og:url: https://daily.dev/posts/data-structures-in-javascript-dictionaries-pkcjokkyu og:image: https://api.daily.dev/og/posts/pKCJokKyU.png og:image:alt: Data structures in JavaScript: Dictionaries 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. # Data structures in JavaScript: Dictionaries **[Flavio Copes](https://daily.dev/sources/flaviocopes)** · 2 min read · 16 upvotes · 1 comments ## Summary ES6 introduced the Map data structure, providing us a proper tool to handle this kind of data organization. What is a Map? It's a data structure that allows to associate data to a key. A WeakMap is a special kind of Map that lets all its items be freely collected. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Community discussion Top comments from developers on daily.dev. **@amol\_8458** · 0 upvotes > concise but thorough explanation of maps. Loved it gonna bookmark it --- Tags: [#general-programming](https://daily.dev/tags/general-programming), [#javascript](https://daily.dev/tags/javascript), [#logging](https://daily.dev/tags/logging) [View this post on daily.dev](https://daily.dev/posts/data-structures-in-javascript-dictionaries-pkcjokkyu) ```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":"Data structures in JavaScript: Dictionaries","url":"https://daily.dev/posts/data-structures-in-javascript-dictionaries-pkcjokkyu","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/data-structures-in-javascript-dictionaries-pkcjokkyu"},"datePublished":"2020-11-08T07:32:14.176Z","dateModified":"2021-10-07T14:17:10.317Z","description":"ES6 introduced the Map data structure, providing us a proper tool to handle this kind of data organization. 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Loved it gonna bookmark it","datePublished":"2020-11-08T12:40:55.605Z","url":"https://daily.dev/posts/pKCJokKyU#c-r4c7GSjpp","author":{"@type":"Person","name":"amol_2488","url":"https://daily.dev/amol_8458","image":"https://avatars2.githubusercontent.com/u/56102962?v=4"}}]} ```