Instruction: Describe the concept of the Event Loop in Node.js and its significance in non-blocking I/O operations.
Context: This question assesses the candidate's understanding of the core mechanism that enables Node.js to perform non-blocking I/O operations - despite JavaScript being single-threaded.
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At its core, the Event Loop is what allows Node.js to execute non-blocking input/output operations — despite JavaScript's single-threaded nature. This means that operations like reading from the filesystem, network requests, or database queries can happen in an asynchronous manner, allowing the main thread to continue executing other code instead of blocking until these operations complete.
The Event Loop operates on a simple mechanism: once Node.js starts its execution process, it initializes the Event Loop, processes the provided script which may make asynchronous API calls, schedules timers, or call process.nextTick(), then begins processing the event loop....
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