--- title: Web Fundamentals: JavaScript Basics | daily.dev description: An introductory chapter in a Web Fundamentals series covering JavaScript basics. Topics include the three variable types (var, let, const), primitive and... canonical: https://daily.dev/posts/web-fundamentals-javascript-basics-uf8dtrsvg twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Web Fundamentals: JavaScript Basics | daily.dev og:description: An introductory chapter in a Web Fundamentals series covering JavaScript basics. Topics include the three variable types (var, let, const), primitive and... og:url: https://daily.dev/posts/web-fundamentals-javascript-basics-uf8dtrsvg og:image: https://api.daily.dev/og/posts/Uf8dtRSvG.png og:image:alt: Web Fundamentals: JavaScript Basics 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. # Web Fundamentals: JavaScript Basics **[Playful Programming](https://daily.dev/sources/playfulprogramming)** · 9 min read · 0 upvotes · 0 comments ## Summary An introductory chapter in a Web Fundamentals series covering JavaScript basics. Topics include the three variable types (var, let, const), primitive and object data types (number, BigInt, string, boolean, undefined, null), arrays, functions (standard and arrow), and classes. Each concept is explained with concise code examples, including a practical CoffeeCup class demonstrating constructors and methods. The next chapter will cover the DOM. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [The Basics of JavaScript](https://daily.dev/posts/the-basics-of-javascript-vp6w47za7) · Medium · 2 upvotes · 0 comments - [Dynamic Data: A Beginner’s Guide to JavaScript Data Type](https://daily.dev/posts/dynamic-data-a-beginner-s-guide-to-javascript-data-type-zy1zgrsrx) · Medium · 3 upvotes · 0 comments - [Medium](https://daily.dev/posts/medium-1u0d8vipk) · Medium · 1 upvotes · 0 comments --- Tags: [#webdev](https://daily.dev/tags/webdev), [#javascript](https://daily.dev/tags/javascript), [#dom](https://daily.dev/tags/dom) [View this post on daily.dev](https://daily.dev/posts/web-fundamentals-javascript-basics-uf8dtrsvg) ```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":"Web Fundamentals: JavaScript Basics","url":"https://daily.dev/posts/web-fundamentals-javascript-basics-uf8dtrsvg","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/web-fundamentals-javascript-basics-uf8dtrsvg"},"datePublished":"2026-03-16T21:48:27.848Z","dateModified":"2026-03-16T21:59:35.181Z","description":"An introductory chapter in a Web Fundamentals series covering JavaScript basics. 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