Because every browser runs JavaScript with no plugins, it's unavoidable for front-end work. Frameworks like React, Vue, and Svelte are built on it, and Node.js extends it to backends, tooling, and APIs, which is why many teams use JavaScript across their whole stack.
Its ubiquity is both strength and weakness: a huge ecosystem and talent pool, but also constant churn and some rough historical edges. Many teams now write TypeScript, which adds type safety on top of JavaScript, for larger projects.
Updated July 2026
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