Instruction: Describe what Service Workers are and their common use cases in modern web applications.
Context: This question assesses the candidate's understanding of Service Workers, their role in enabling advanced features like offline support, and their usage in progressive web apps (PWAs).
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At its core, a Service Worker is a type of web worker. It's a JavaScript file that operates in a separate thread from the main browser thread, enabling it to intercept network requests, cache or retrieve resources from the cache, and deliver push messages. This ability is what makes Service Workers a cornerstone technology for Progressive Web Apps (PWAs), as they enable applications to load instantly and reliably, regardless of network state—significantly enhancing the user's experience by making web applications feel more like native apps.
Common Use Cases:...
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