Svelte

Definitions

1. Svelte is a frontend framework created by Rich Harris that takes a fundamentally different approach to building user interfaces by shifting work from runtime to compile time. Unlike React and Vue, which ship a runtime library to the browser and do work in the virtual DOM, Svelte compiles your components into highly efficient, imperative JavaScript at build time that directly manipulates the DOM. This results in smaller bundle sizes and faster performance because there is no framework overhead in the browser. Svelte components are written in .svelte files that combine HTML, CSS, and JavaScript in a single file with a syntax that feels close to plain HTML. Reactivity is built into the language itself: assigning to a variable automatically triggers UI updates without requiring special functions or hooks. Svelte also includes built-in transitions, animations, and scoped CSS. SvelteKit, the official application framework, provides routing, server-side rendering, code splitting, and deployment adapters. Svelte has been gaining rapid adoption and was the foundation for the redesign of the New York Times interactive graphics platform.

   In plain English: A web framework that turns your components into tiny, efficient JavaScript at build time instead of shipping a big runtime library to the browser.

   Example: "Svelte compiles the reactivity into plain assignments — you just write `count += 1` and the DOM updates automatically, no useState needed."

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